" \ r J 



■BBa 



NITR0WS 0XIDE 




RD 86 
.N7 G9 
Copy 1 




•V:'-"'-V.v , V,- '■ 







M 



mi 



Nitrous Oxide ; 



ITS PROPERTIES, METHOD OF ADMINISTRATION 
AND EFFECTS. 



S. H. GUILFORD, 1. M., D. D. S., 



PROFESSOR OF OPERATIVE AND PROSTHETIC DENTISTRY AT THE PHTLA 
DELPHIA DENTAL COLLEGE. 



o- r 




Dr 



1° 




PHILADELPHIA! 
SPANGLER & DAVIS. PRINTERS, 



v 



Entered according to Act of Congress in the year 1887, by 

S. H. GUILFORD, 

in the office of the Librarian of Congress at Washington, D. C. 



111. 



"The knife of the surgeon is steeped in the waters 
of forgetfulness, and the deepest furrow in the knotted 
brow of agony is forever smoothed away." 

O. W. Holmes. 



"If America had contributed nothing more to the 
stock of human happiness than anaesthetics, the world 
would owe her an everlasting debt of gratitude." 

S. D. Gross. 



V. 



PREFACE, 



jS\HE preparation of this Manual was prompted 
' by the feeling, expressed by others and felt 
by the writer, that such a work would prove a 
benefit to the student and young practitioner. 
This feeling was emphasized by the fact that the 
last practical work upon the subject, published in 
this country, has been out of print for sixteen 
years. 

The record that nitrous oxide has made for 
itself since its. introduction proves it to be the 
safest of all anaesthetics, and the one most suitable 
for minor operations in dental surgery. 

Its employment is being extended so rapidly 
that a better knowledge of its properties and 
effects seemed necessary to enable novices to 
secure its full advantages without incurring undue 
risk of accident. With this end in view the 



VI. 



author has endeavored to treat the subject in a 
thoroughly practical manner, giving full details of 
preparation, administration and extraction under 
its influence, and at the same time indicating the 
manner of dealing with any emergencies that 
might arise in connection with its employment. 

The last two chapters, treating of the combina- 
tion of anaesthetic agents and of legal questions 
related to the administration of anaesthetics, will, 
it is hoped, prove to be of special value to those 
for whom the work has been prepared. 

The author would acknowledge the kind assist- 
ance of Dr. E. C. Kirk in the revision of proof, 
and the courtesy of publishers and dealers in 
furnishing certain cuts, which are credited to 

them in place. 

S. H. G 



Vll. 



CONTENTS 



Chapter. Fage 

1. History, . . . . . 1 

2. Chemical Properties, . . . .5 

3. Physiological, Action, ... 8 

4. Relative Safety, . . . .22 

5. Advisability of Administration in Special 

Cases, . , . . .26 

6. Manufacture, . . . . .32 

7. Inhalers and Accessory Appliances, . 45 

8. Administration, . . . . .52 

9. Extraction during Anaesthesia, . 61 

10. Accidents and Emergencies, . . .70 

11. Combined Anaesthetics, ... 79 

12. Legal Considerations, . . .87 



NITROUS OXIDE. 



CHAPTER I. 

HISTORY. 

The discovery of nitrous oxide, or nitrogen prot- 
oxide, with its valuable properties and resultant 
benefits to mankind, was not the work of one man 
or of one time. Like many other valuable discov- 
eries and inventions, the credit of its origin and suc- 
cessful use is divided among several, each of whom 
contributed his part toward the final result. 

Thus the discovery of the gas, per se, was made 
by Priestley in 1Y76 ; its exhilarating and analgesic 
effects were noticed by Davy in 1800 ; while its full 
and practical value as a true anaesthetic was first 
demonstrated by Dr. Horace Wells, in 1844. Davy 
suggested that '" as nitrous oxide, in its extensive 
operations, appears capable of destroying physical 
pain, it may probably be used with advantage dur- 
ing surgical operations in which no great effusion 
of blood takes place." From 1800, when the above 
prophetic suggestion was made, up to the time of its 
introduction as an anaesthetic, in 1844, its anaesthetic 



2 NITROUS OXIDE. 

properties received no attention and called forth no 
experimentation of which we have any knowledge 
on the part of the medical or dental professions. 

Its exhilarant properties, however, were at once 
taken advantage of and demonstrated both in the 
class-room and on the lecture platform. 

Both abroad and in this country during those 
forty-four years lecturers appeared from time to 
time in various places discoursing upon the peculiar 
properties of this u laughing gas r? and exhibiting 
its effects upon subjects, to the amusement of the 
audience and the pecuniary benefit of the exhibitor. 

Mr. G. Q. Colton, of Xew York, one of the more 
prominent lecturers, gave an entertainment of this 
kind at Hartford, Conn., in December, 1844. Dr. 
Wells, a dentist of that city, was present as a spec- 
tator, and noticed the freedom from pain that at- 
tended the accidental injury of one of the subjects. 
This fact deeply impressed Dr. Wells, who was led 
to believe, from what he had seen, that teeth might 
be extracted without pain under its influence. 

Determined to test the matter upon his own per- 
son by having a tooth extracted, he arranged with 
Mr. Colton to come to his office on the following 
day to administer the gas, while Dr. John M. 
Riggs, another dentist of the same city, was invited 
to be present and perform the operation. Dr. Wells 
inhaled the gas at the hands of Mr. Colton, and Dr. 
Riggs extracted the tooth. On recovering, he 
declared that lack of consciousness and absence of 



HISTORY. 6 

pain were both complete, and then and there prophe- 
sied a great future for the new and only true anaes- 
thetic. 

Dr. Wells immediately communicated his discov- 
ery to others, and began, in conjunction with Dr. 
Riggs, an extended series of experiments with the 
new agent. He used it freely during the whole 
remaining period of his dental practice, and other 
dentists, particularly in the Eastern States, adopted 
its use. 

Eminently satisfactory as it had proven in dental 
operations, Dr. Wells was not content to allow its 
use to rest there. He believed that there was a 
great field for it in general surgery, and began 
urging its introduction in that direction. In all 
minor operations, and some major ones, it answered 
well, as it had in those pertaining to the mouth. 
There were, however, two serious objections to its 
use in general surgery. One was the care and 
knowledge necessary for its proper preparation, and 
the other its bulkiness, rendering it difficult to trans- 
port from place to place. 

These objections led Dr. Wells to cast about for 
some other anaesthetic that would be free from 
them. Sulphuric ether was known to possess cer- 
tain anaesthetizing properties, and Dr. Wells at 
once began to experiment with it. His efforts and 
experiments to prove its value as a practical anaes- 
thetic in 1845 were quite successful, and others 
then taking it up, it soon came into general use in 
surgery, and has so continued ever since. 



4 NITROUS OXIDE. 

It will thus be seen that for the practical intro- 
duction of both nitrous oxide gas and sulphuric 
ether as anaesthetic agents the world in general is 
laid under obligations to Dr. Horace Wells, an 
American dentist. He died in 1848, too early to 
receive the honors and blessings of grateful hu- 
manity, but with his name will ever be linked the 
grandeur of his achievements. 

From his clay to ours nitrous oxide has been the 
adopted anaesthetic of the dental profession. The 
duration of its effects, though brief, is sufficient for 
our purposes, while its comparative freedom from 
danger makes its use desirable for all minor opera- 
tions. 

Its employment became more general year by 
year, and its extension would have been more rapid 
but for the difficulty attending its manufacture. In 
the earlier days it was made by the individual using 
it, which required a rather expensive and cumbrous 
apparatus, besides demanding a fair amount of 
chemical knowledge to ensure its freedom from dele- 
terious contaminations. Within the past dozen 
years, however, these objections to its more general 
use have been overcome by its careful manufacture 
on a large scale by experienced and skillful hands 
and its compression into liquid form in strong iron 
bottles or cylinders. Its compactness and conven- 
ience, together with its absolute purity in this form, 
have greatly extended its use, and must continue so 
to do for all dental and many surgical purposes. 



CHEMICAL PROPERTIES. 



CHAPTER II. 

CHEMICAL PROPERTIES. * 

Nitrous oxide is a transparent, colorless gas, of 
slightly sweetish taste, and faint but pleasant odor. 
Its chemical symbol is N 2 0, indicating that it is 
composed of two equivalents by volume of nitro- 
gen to one of oxygen. The symbol was formerly 
written N 0, because it was known that in this gas 
nitrogen and oxygen were combined in their lowest 
combining quantities, but as oxygen is bivalent and 
nitrogen in this compound is univalent, it is properly 
written N 2 0. Although known as nitrous oxide, 
it is in reality hypo-nitrous oxide, nitrous oxide 
proper being represented by the symbol N 2 3 . Its 
specific gravity is 1.527, one hundred cubic inches 
weighing 47-29 grains. 

Under a pressure of 50 atmospheres at 45° F. it 
is condensed into a clear, transparent liquid, and at 
150° F. below zero this liquid solidifies. Nitrous 
oxide is not a simple mixture of its two constituent 
gases, but a definite chemical compound in which 
the properties of the original gases are lost and new 
ones peculiar to itself are developed. Proof of this 



6 NITROUS OXIDE. 

is found in the fact that the gas has both a taste and 
a smell, while air, composed of the same elements, 
has neither. Thus, also, hydrogen and oxygen, 
when simply mixed, can be inhaled for a time with- 
out ill effects, while water, a chemical compound of 
the same elements, is totally irrespirable. Nitrous 
oxide wilJ also support combustion, provided the 
substance introduced into it be first heated suffi- 
ciently to resolve the compound into its original ele- 
ments. 

It may be produced from various substances, but 
is most conveniently and profitably manufactured 
from ammonium nitrate. This salt, when subjected 
to heat, first melts, then boils and undergoes decom- 
position, the gas being liberated at about 400° F. 
In its decomposition only nitrous oxide and water 
are formed, thus : 

JHJ 3 + heat = 2 H 2 + ]S T 2 0. 

Impurities are sometimes found in the commercial 
salt, the most common and dangerous one being 
chlorine. As this is somewhat difficult of separa- 
tion from the nitrous oxide, it is better to see in ad- 
vance that it is not present in the salt. Ammonium 
nitrate is readily soluble in five or six times its bulk 
of water. If such a solution be made, and a solu- 
tion of argentic nitrate be added, the presence of 
chlorine will be indicated by the mixture becoming 
clouded, due to the formation of argentic chloride. 
Should the solution remain clear we may be sure 
that chlorine is not present. All new lots of the 
salt should be thus tested before using. 



CHEMICAL PROPERTIES. 7 

Nitrous oxide is somewhat soluble in water, the 
latter taking up its own bulk or more of the former. 
It may again be eliminated by subjecting the water 
to a moderate degree of heat. Besides combining 
to form nitrous oxide, the two gases, nitrogen and 
oxygen, unite in different proportions, forming a 
series of chemical compounds as follows : * 

N2 O, Hypo-nitrous oxide. 

N 2 2 , Nitrogen di- oxide. 

N 2 3 , Nitrous oxide. 

N 2 4 , Nitrogen tetra-oxide. 

N 2 5 , Nitric oxide. 
Although nitrous oxide, in composition, differs 
from all other chemical bodies, it is somewhat anal- 
ogous to atmospheric air. They have the same con- 
stituent elements, both are supporters of combus- 
tion under certain conditions, and both may be re- 
spired in proper quantities without harm. They 
differ from each other, however, both in the propor- 
tion of their elements and in the character of their 
association. Thus, while nitrous oxide contains 
one-third of oxygen to two-thirds of nitrogen, 
atmospheric air is composed of one-fifth of oxygen 
to four-fifths of nitrogen. In addition to this, as 
previously stated, in nitrous oxide the elements are in 
chemical combination, whereas in air they are simply 
associated mechanically. 

Nitrous oxide is more respirable than oxygen and 
possesses the property of anesthetization, a quality 
totally lacking in simple oxygen. 



* Barker's Chemistry. 



NITROUS OXIDE. 



CHAPTER III. 

PHYSIOLOGICAL ACTION. 

The exact manner in which nitrous oxide acts 
upon the system to produce its well-known effects 
has never been clearly demonstrated. Like its prin- 
cipal rivals, sulphuric ether and chloroform, a great 
variety of opinions has always existed in the minds 
of the various investigators as to how and why 
these effects are produced. 

The outward manifestation of their action is, in 
the case of each one, well marked and clearly de- 
fined, and from these manifestations we know to a 
great extent what organs are affected ; but the pre- 
cise manner in which these organs are operated 
upon by the anaesthetic agent must be left for the 
future to determine. 

All of these three most commonly used agents 
have many points of similarity in their action, but 
they differ widely both as to the manner in which 
they affect the various organs and the order in 
which these organs become affected in the course of 
anesthetization. Thus, each one, when adminis- 
tered in quantity and manner consistent with its 



PHYSIOLOGICAL ACTION. 9 

nature and the condition of the patient, will pro- 
duce the same effect — anaesthesia; and each one, 
also, when the administration is carried beyond 
this point, may or will produce death. 

So, too, we know that the action of the lungs, 
heart and brain are modified by them through the 
agency of the circulating medium, the blood ; but 
each one of these organs is affected differently, in 
degree, in order, and probably in manner, by the 
different agents employed. 

The external symptoms, as they manifest them- 
selves, indicate that the individual passes through 
three stages in the process of anesthetization. First, 
we have exhilaration, or stimulation, then excite- 
ment, and afterwards relaxation, accompanied by 
suspension of sensation and motion. 

These stages are very well marked in the admin- 
istration of ether, while they are less so with chlo- 
roform and nitrous oxide. 

In this fact lies to a great extent the comparative 
safety of ether, since it enables the operator to 
readily determine how far the patient is being car- 
ried, and to cease the administration at the proper 
moment. Chloroform is more dangerous, because 
with it these symptoms are often confluent or follow 
each other so rapidly that the limit of safety may 
readily be passed without proper warning. 

Nitrous oxide differs from all other anaesthetics in 
several important particulars, which are worthy of 
being mentioned in some detail. First of all, it is 



10 NITROUS OXIDE. 

agreeable to the individual while being inhaled, for, 
aside from its slightly sweetish taste, the patient 
would not be able to distinguish it from atmospheric 
air. Both ether and chloroform in the first stage of ad- 
ministration produce a marked irritating effect upon 
the respiratory track that is both unpleasant and 
alarming to the patient, since it produces a feeling 
akin to suffocation. Xo such feeling is produced by 
nitrous oxide ; hence, we are enabled to exhibit it in 
full quantity from the very beginning without ad- 
mixture of air, a very important matter in the pro- 
duction of narcosis with this agent. 

Another important property of nitrous oxide is 
the rapidity with which it produces its effects. 
With a more dangerous agent this would not be 
desirable, owing to the attendant risk of passing 
the limit of safety without proper warning ; but, 
with so safe an agent as this, such risk is reduced to 
its smallest proportions. Besides this, abundant 
experience has proven that the best results are ob- 
tained from nitrous oxide when the patient is under 
its influence for the shortest time. This is probably 
due to the fact that in such case the oxygenation of 
the blood is interfered with for a shorter period. 

By the administration of nitrons oxide in fall 
quantity the average patient is fully anaesthetized in 
thirty seconds. This condition continues complete 
for about a minute after the administration is sus- 
pended, after which about another half minute 
elapses before the patient is fully restored to con- 



PHYSIOLOGICAL ACTION. 11 

sciousnesss. The whole time thus occupied from 
end to end for any dental operation does not usually 
exceed two minutes. The rapid elimination of the 
gas from the system during recovery is a feature 
peculiar to itself and greatly appreciated by both 
patient and operator, for, beside the saving of time 
to both, it relieves the latter from the nervous strain 
always existing when his patient is in an uncon- 
scious condition. 

Another peculiarity in the action of nitrous oxide 
is that when anesthetization is complete, sensation 
is completely suspended, but consciousness may not 
be entirely so, and while there is suspension of 
muscular action, there is no general muscular relax- 
ation. 

With all true anaesthetics, while their influence is 
complete, there must, of necessity, be absolute sus- 
pension of sensation ; but with most of them there 
is also complete suspension of consciousness at- 
tended with absolute muscular relaxation. 

A patient fully under the influence of ether or 
chloroform, besides being insensible and totally un- 
conscious, has his muscular system so thoroughly 
relaxed that it is often difficult to keep the body up- 
right in the chair, and the arm, if raised, will fall 
limp by the side. Under the influence of the gas," 
however, the patient easily maintains an erect posi- 
tion, and the arm, if lifted and released, will either re- 
main upright or descend slowly to its former posi- 
tion. So, too, patients, on recovering from the 



12 NITROUS OXIDE. 

effects of the gas, will often be able to tell how many 
teeth were extracted and the order in which they 
were removed, although they had been entirely ob- 
livions to any sensation of pain. They sometimes 
also speak of a desire to pnt forth muscular effort 
while under the influence aud their inability to do 
so, comparing their feelings in this respect to those 
attending an attack of incubus or nightmare. 

The ultimate effects of most anaesthetics are seda- 
tive or depressing in their character, for, while un- 
der the early influence of their exhibition, the action 
of the heart is increased, as shown by the more 
rapid pulse, later on, the pulse usually falls below 
its normal number of beats. With nitrous oxide 
this is not the case. Under its influence the p n 
is more rapid, and remains more or less so during 
the continuance of the effect. Proof of this is 
afforded in the careful recording of the action of the 
pulse in one hundred cases by Dr. J. D. Thomas 
of this city. In one case it rose to one hundred and 
forty-four, in several others to one hundred and 
twenty-eight, while in a few there was little or no 
change. 

A notable contrast between nitrous oxide and 
ether or chlorofom is afforded in their after 
effects. The administration of ether gener- 

ally and chloroform quite frequently followed by 
nausea, while both are about equally attended with 
great subsequent debility of the patient, frequently 
lasting for hours and sometimes for days. This is 



PHYSIOLOGICAL ACTION. 13 

in obedience to a well-recognized principle in the 
action of medicines in general. 

Dr. George B. Wood, in his Pharmacology and 
Therapeutics, says : " One of the laws of all stimu- 
lation, whatever may be its degree, is that it is fol- 
lowed by a depression proportionate, at least proxi- 
mately, to the previous exaltation of the function or 
functions excited. " 

Nitrous oxide, in its action, seems to set aside or 
evade this law, for its exhibition, when properly 
directed, is not followed by any noticeable depres- 
sion. The patient, after his quick recovery from its 
influence, feels as well and strong as before, and is 
able to attend to his usual duties without any loss 
of time or feeling of languor. Nausea, too, follow- 
ing its administration is almost unheard of, even 
though given after a hearty meal. The author, in 
his extended experience with this agent, can recall 
but three cases where nausea followed the inhala- 
tion of the gas. 

It has been charged against the gas by a few (the 
late Prof. George T. Barker among the number) 
that its after effects, although not serious, were 
often uncomfortable and long-continued, manifest- 
ing themselves in a form of cephalalgia and general 
debility. 

It is believed, however, by those who have most 
carefully watched the effects of the gas through a 
series of years, that in the very few such cases 
brought to light the unpleasant results were 



14 NITROUS OXIDE. 

attributable either to nervous shock following ex- 
tensive operations on patients of delicate nervous 
organization ; to the impurity of the gas ; to its in- 
judicious administration in too great quantity, or to 
the inhalation of carbonic acid gas exhaled from the 
lungs into a rubber bag from which the nitrous ox- 
ide was being given. 

The two principal theories that have obtained in 
regard to the physiological action of nitrous oxide 
are hyper-oxidation and hypo-oxidation. The ad- 
vocates of the former theory believe that the anaes- 
thetic effects of the gas are due to the fact that in its 
administration the lungs are supplied with a greater 
relative volume of oxygen than they are accustomed 
to receive, and this being carried to the brain by the 
blood produces there a condition of over-stimulation, 
which exalts or raises the nervous centres above the 
point of sensation. They base their belief on the 
fact that nitrous oxide contains more oxygen than 
atmospheric air, and oxygen in its action produces 
a stimulating effect. This stimulating effect, which 
to them argues a superabundance of oxygen in the 
blood, is noticeable in the first stages of anestheti- 
zation by this agent. 

Those who hold to the theory of insufficient oxi- 
dation claim that the gas acts principally by occu- 
pying the space in the lungs normally held by the 
oxygen of the air, and to its exclusion, thus prevent- 
ing the proper oxidation of the blood, followed, in 
consequence, by suspended sensation, muscular in- 



PHYSIOLOGICAL ACTION. 15 

action, and the production of a condition in the sys- 
tem closely related to asphyxia. 

The change in the color of the blood during the 
administration of the gas, as shown in the lips, eye- 
lids and face, shows conclusively, they say, that the 
oxidation of the blood has been interrupted or inter- 
fered with. 

The first theory had many supporters in the ear- 
lier days, but they rapidly fell away when it was 
shown to be incorrect. It was based upon the be- 
lief that nitrous oxide was a supporter of combus- 
tion at normal temperature, which proved to be a 
fallacy. It doubtless would be a supporter of com- 
bustion if it were a mere mixture readily separable ; 
but, being a chemical compound, with properties 
peculiar to itself, and not resolvable into its original 
elements except at a high heat, it could not support 
combustion by virtue of the amount of oxygen it 
contained. 

Dr. Thomas W. Evans, of Paris, writing upon 
this subject, says : * " The fact that nitrous oxide 
contains a greater proportion of oxygen than atmos- 
pheric air is no evidence, even a priori, that it pos- 
sesses a greater oxygenating activity. The deut- 
oxide of nitrogen is, as compared with nitrous oxide, 
doubly rich in oxygen ; but it is not only immediately 
fatal to animal life, but is even incapable of supporting 
combustion. The physical properties of nitrous 



*Dental Cosmos, Yol. XL, p. 286. 



16 NITROUS OXIDE. 

oxide differ widely from those of oxygen, as well as 
from those possessed by any mixture of oxygen and 
nitrogen, and the physiological effects of the gas are 
equally distinctive. " 

The theory of insufficient or hypo-oxidation is the 
one having the greater number of supporters at the 
present time. It has superseded the previous theory 
on account of its greater reasonableness and because 
the physical facts of the case support it. 

If nitrous oxide is not an oxygenating agent or 
supporter of combustion, its presence in the lungs, 
to the exclusion of atmospheric air, would tend to 
prevent oxidation of the blood, and this would 
cause all the blood to circulate as venous, producing 
lividity of the countenance and gradually stupefy- 
ing the brain and nerve centres so that narcosis or 
insensibility would supervene. 

Now, these effects are all noticeable to a certain 
extent in the progress of anesthetization, and it is 
but reasonable to presume that they are partly pro- 
duced by the gas in the manner described. 

Prevention of oxidation of the blood, however, 
would not be sufficient to account for all the mani- 
festations attending the administration of the gas, 
and it has therefore come to be believed that the 
agent also produces a specific stimulating effect, 
upon certain nerve centres, which has not been 
clearly defined. 

As showing the opinions held by recent authori- 
ties in regard to the physiological action of nitrous 
oxide, we give the following : 



PHYSIOLOGICAL ACTION. 17 

Prof. George Johnson says : * " Nitrous oxide is 
a rapidly acting anaesthetic, causing complete un- 
consciousness in less than a minute. At a high 
temperature it is an oxidizing agent, but at the 
temperature of the body it gives up no oxygen, but 
is exhaled again unchanged. When inhaled in place 
of atmospheric air it rapidly replaces the oxygen of 
the blood, and this being done, the functions of the 
brain are completely suspended and there is a state 
of profound coma, which quickly passes off when air 
is again allowed to enter the lungs. " Dr. Robert 

Amorv coincides with this view. 

«/ 

Prof. H. C. Wood, Jr.,f says that in anestheti- 
zation by nitrous oxide there is " partial capillary 
stasis in the brain and diminished oxidation of the 
blood." 

Dr. Turnbull J says : " After numerous experi- 
ments and observations on man and animals, I have 
arrived at the following conclusions : 

1. Nitrous oxide gas has a very limited range 
when given alone, owing to the rapidity of its action 
and still more rapid elimination. 

2. It acts directly upon the cerebrum and muscu- 
lar apparatus almost simultaneously. 

3. It produces regular and progressive modifica- 
tion in the action of the heart and capillaries of the 

*Medical Times and Gazette, April 3, 1869 ; Turnbull, 
p. 178. 
fDental Cosmos, Yol. XIII., p. 207. 
X Anaesthetic Manual, 2d. Ed., p. 198. 



18 NITROUS OXIDE. 

skin, and, if carried to a greater extent, it affects 
the spinal axis, and lastly the cerebrum and medulla 
oblongata with suspension of respiration and circu- 
lation, and finally death. 

4. Death in no case occurs without premonitory 
symptoms, and if respiration should cease for even 
a half to one minute, resuscitation is yet possible." 

Dr. J. W. White, in an editorial in the Dental 
Cosmos * on the death of a lady alleged to have 
been caused by the inhalation of nitrous oxide gas, 
gives a very clear and concise statement of his 
views as to the physiological action of the gas. 
He says : " The conviction of the writer, based on 
personal experience repeated hundreds of times, as 
well as on observation and reflection, is that nitrous 
oxide, when inhaled, acts primarily by a specific 
stimulant effect on the centres of innervation (over- 
stimulation and consequent depression if continued) 
and secondarily by preventing the oxygenation of 
the blood. That the inhalation of nitrous oxide, 
if continued, produces, by some method of action, 
no matter what its primary effect, progressive de- 
pression of vital functions, which tends to death, 
and in which the anaesthesia or temporary uncon- 
sciousness sought, is a more or less clearly de- 
fined step in the downward path there is no doubt. 
Immunity from danger can at the best be assured 
only by an intelligent and watchful guard, and its 



*Vol. XIV., p. 311. 



PHYSIOLOGICAL ACTION. 19 

exhibition should be suspended while yet the centres 
governing respiration and circulation are not too 
profoundly impressed.' ' 

One feature connected with the anaesthetic state, 
of vital importance to the operator, is the effect that 
the various agents have upon the urino-genital or- 
gans. Fortunately, this effect is not often pro- 
duced, or, at least, manifested, but when it is it may 
be the means of involving the operator in serious 
difficulty, unless he has taken the precaution to pro- 
tect himself by the presence of a third party. 

As in dreams during sleep, where portions of the 
brain are active while others are at rest, so in anaes- 
thesia, where it is not profound, the patient in most 
cases has dreams of one sort or another, the charac- 
ter of which no one can foresee. In many cases 
they are erotic in character, and may so strongly 
impress the mind of the patient as to pro- 
duce the conviction, upon restoration to conscious- 
ness, that the circumstances were real and not im- 
aginary. In this way a perfectly honest patient 
may place an equally upright operator in a most 
embarrassing situation by accusing him of that of 
which he is entirely innocent. Cases of this kind 
have occurred, and are on record, resulting, in cer- 
tain instances, in legal proceedings which proved 
detrimental to the character of the operator and 
materially injurious to his professional interests. 
These are alluded to more fully in chapter XII. 

These hallucinations, of which the operator must 



20 NITROUS OXIDE. 

ever stand in great fear, have occurred in connec- 
tion with the administration of all the principal 
anaesthetics, but whether they occur more frequently 
under the influence of nitrous oxide, we have no 
means of ascertaining. 

Prof. Barker * says he never met with a case in 
which the aphrodisiac effect was noticeable. 

Ziegler says : f" Nitrous oxide has a special 
tendency to these (urino-genital) organs and exerts 
a powerful influence over their functions. " Again, 
he says : " Moreover, through its powerful aphro- 
disiac effects, it may intensify sexual desire to such 
a degree as to cause unpleasant exposure or even 
serious trouble." 

Prof. Stellwagen, in his American revision of 
Coleman J quotes Dr. Johnston, of Brooklyn, as 
follows : " Anaesthetics do stimulate the sexual 
functions. The ano-genital region is the last to 
give up its sensitiveness. Dentists or surgeons 
who do not protect themselves by having a third 
person present do not merit much sympathy." 

The author, in the course of his personal expe- 
rience, has met with a few cases. in which the erotic 
effect was most marked. In one instance the 
patient (a man) by his actions gave unmistakable 
evidence of the vile character of his dream. Such 



^Instructions in Nitrous Oxide. 
fResearches on Nitrous Oxide, pp. 23-51. 
^Coleman's Dental Surgery, p. 336. 



PHYSIOLOGICAL ACTION. 21 

effects are, of course, due to the stimulative effects 
of the anaesthetic. 

Another result, less serious in character, though 
quite undesirable and annoying, sometimes follows 
or attends the administration of an anaesthetic. It 
is the voidance of the contents of the bladder or 
rectum, due to the muscular relaxation of their 
sphincters. 

Almost every anaesthetist has met with occasional 
instances of this kind, and they are more common 
with children than adults on account of the irregu- 
larity of their habits. As there is less muscular 
relaxation produced by nitrous oxide than by ether 
or chloroform, such accidents are more likely to be 
met with in the administration of the latter agents. 
As a preventive measure, in the case of children, it 
is well to request the parent or attendant to see that 
the organs are evacuated before the administration. 



22 NITROUS OXIDE. 

t 



CHAPTER IV. 

RELATIVE SAFETY. 

In considering the safety of anaesthetic agents, 
and of nitrous oxide in particular, it must be borne 
in mind that the anaesthetic state is a pathological 
and not a physiological one. In entering it the pa- 
tient gradually passes out of his natural condition 
into one that is unnatural and abnormal. The vital 
functions are altered and interfered with, and such 
interference, as in disease, constitutes a departure 
from the basis of safety. If such departure be 
slight or limited no ill result will usually follow, but 
if it be carried to a great length serious conse- 
quences may and often do result. 

Dr. Squibb, one of our best authorities on anaes- 
thetics, says : " The line of greatest safety in prac- 
tice is to regard the difference between anaesthesia 
and death as a difference in degree only. The con- 
dition may" be partial, full, profound or fatal, but 
with no distinct boundary lines between the degrees. 
The two intermediate degrees or stages constitute 
anaesthesia proper, and the full anaesthesia is gener- 
ally required in surgery, while the stage of partial 
anaesthesia is generally sufficient in medicine. " 



RELATIVE SAFETY. 23 

Bearing in mind the fact that all anaesthetics hav.e 
associated with them the element of danger, and that 
when given it must be with a full understand- 
ing of the possible serious results, it follows that 
they should not be administered carelessly or by 
anyone who does not thoroughly understand their 
properties and action. 

Of the various anaesthetic agents thus far intro- 
duced, nitrous oxide is on all hands conceded to be 
by far the safest. It has undoubtedly been used 
the greatest number of times ; has probably saved 
the greatest aggregate amount of pain, and has pro- 
duced by far the fewest deaths. 

In 18^0 Prof. E. Andrews * gave the following 
estimate of the relative danger from different anaes- 
thetics : 

Sulphuric ether, 1 death to 23,204 administrations. 

Chloroform, 1 " "2,723 

Mixed chloroform 
and ether, 1 " "5,588 

Bichloride of 
Methylene, 1 " "7,000 

Nitrous oxide, No deaths in 75,000 " 

One of the best evidences of the relative safety of 
nitrous oxide is the fact that in one office in the city 
of Philadelphia (Colton Dental Association suc- 
ceeded by Drs. F. R. and J. D. Thomas) the gas 
has been administered for the extraction of teeth 
and minor surgical operations one hundred and 



*Chicago Medical Examiner. 



24 NITROUS OXIDE. 

forty-seven thousand times without a single death or 
serious consequence. 

During the past twenty-two years the author has 
administered it many thousands of times without a 
single unfavorable result. Its introduction and use 
have grown year by year, until there is scarcely a 
village in the more populated States of America 
where it is not administered daily in one or more 
dental offices, while in all of the larger cities there are 
offices wholly devoted to its administration. Con- 
sidering then its wide-spread use, the varying ages 
and physical conditions of those to whom it is admin- 
istered, and the fact that in many cases those using 
it have had no proper instruction as to its properties 
or manner of administration, we cannot but wonder 
at the few ill results that have followed its use. 
Up to the present time but four deaths have fol- 
lowed its administration in this country, and, as all 
of these occurred during the time that the gas was 
made in the office of the one using it, it is more 
than probable that some, if not all of them were at- 
tributable to impurities in the gas, resulting from im- 
perfect preparation. So far as the author has been 
able to ascertain, no deaths have as yet resulted 
from the use of the liquified gas. 

Dr. Squibb, in a lecture on anaesthetics before the 
Medical Society of the State of New York, says : 
" Nitrous oxide wa a the first anaesthetic, and the 
safety and certainty of its effects, even in inexpe- 
rienced hands, for all momentary operations, and 



RELATIVE SAFETY. 25 

the promptness with which persons recover from its 
effects, render it, perhaps, the most important of 
all anesthetics, because destined to relieve a greater 
aggregate amount of pain, with greater safety, than 
any other agent." 

Dr. Turnbull* says : " Nitrous oxide is the safest 
of all anaesthetics." 

Mr. Underwood, of London, says : f " Nitrous 
oxide gas is the best anaesthetic at present known to 
the profession. The risk to life is so small that it 
may safely be said that, supposing a cardiac condi- 
tion existed that rendered nitrous oxide gas a dan- 
gerous agent, in such a case any operation, even 
the extraction of a tooth, without an anaesthetic, 
would be attended with still greater danger. To 
put the case in other words, every short operation 
becomes less dangerous to life when performed 
under gas than when the anaesthetic is not em- 
ployed. The gas, administered with ordinary care 
by some one whose entire and undivided attention 
is devoted to its administration, renders less, and 
not greater, the risk to life, if any such risk be sup- 
posed to attend the extraction of a tooth." 



*Op. Git., p. 204. 

[Notes on Anaesthetics, 1st Ed., pp. 12-13, 



26 NITROUS OXIDE 



CHAPTER Y. 

ADVISABILITY OF ADMINISTRATION IN SPECIAL CASES. 

Before entering npon the subject of the adminis- 
tration of nitrous oxide gas, it may be well to con- 
sider first certain abnormal or other conditions of 
the system in which the advisability of its exhibi- 
tion might be questioned. 

Foremost among these are those relating to the 
heart and lungs. Any affection of these important 
organs, while it might not contra-indicate the use 
of the agent, would certainly introduce an element 
of possible danger that should be thoroughly under- 
stood and, as far as possible, guarded against. The 
administration of the gas to patients affected with 
valvular disease of the heart or phthisis has always 
been considered inadvisable, although the rarity of 
a death directly traceable to either of these condi- 
tions, and the further fact that the gas has undoubt- 
edly been administered in many cases where these 
conditions were not recognized, have caused them 
to be considered less dangerous than they once were. 

Underwood says: * " Heart disease is no draw- 



*Loc. Cit,, p. 29. 



ADVISABILITY OF ADMINISTRATION. 27 

back to the administration of nitrous oxide. Very 
fatty, weak hearts have been supposed to expose 
the patients to some risk, but there has never been 
a fatal case traceable to this cause. Moreover, as 
this condition is not diagnoseable during life, it is 
futile to consider it. Organic disease does not in- 
volve any additional risk whatever to the patient. " 

Coleman says : f " Patients who have suffered 
from acute rheumatism, resulting in damaged valves 
of the heart, etc., appear to take nitrous oxide as 
well as ordinary patients, but the appearance of a 
lady affected with cyanosis was such that we should 
in future decline to administer it in similar cases. 
Those with weak and fatty hearts must ever be 
unsafe subjects for the gas or other anesthetics. 
Should we have a knowledge or suspicion that we 
have to deal with a patient so circumstanced, we 
should, besides redoubling our precautions with 
regard to careful observation of all symptoms, pay 
especial attention to the conditions of the pulse. 
We strongly recommend operating only whilst the 
patient is fully anaesthetized,* for the reason that 
there will be less chance of arresting the heart's ac- 
tion through shock." 

Turnbull says : * " Those who are less skilful 
and inexperienced should reject cases of great physi- 
cal exhaustion or patients with a feeble or fatty 
heart." 



|P. 336. 
*P. 167. 



28 NITROUS OXIDE 

While it is most important to ascertain before- 
hand, either through our own examination or that 
of a physician, whether there be any abnormal con- 
dition of the patient's heart, we need not be deterred 
from the administration by the patient's own state- 
ment of the condition of his or her heart, for the 
average patient, when questioned, will in nearly all 
cases confess to some derangement of that organ. 
Palpitation, caused by excitement or slight exertion, 
is most common and harmless, and yet the unin- 
formed patient will be most likely to construe the 
condition into a serious one peculiar to himself. 
Such persons can generally be best comforted and 
assured by placing one's ear or the stethoscope to 
the patient's chest and noticing the character of the 
pulsation. 

In phthisis the danger will be more or less great 
according to the extent of the disease. In the ear- 
lier or middle stages there will be no real danger, 
but the patient, owing to debility and the oblitera- 
tion of lung tissue will require less than the ordi- 
nary quantity of gas to produce anaesthesia. In 
advanced stages of the disease it is better to avoid 
the administration, if possible, but if the suffering 
of the patient can be alleviated in no other way, we 
should give it with the greatest care, noticing well 
the respiration and pulse, carrying the patient only 
to the stage of insensibility and not beyond it. 
That it is proper to give it, as a last resort, under 
the last mentioned circumstances, cannot be ques- 



ADVISABILITY OF ADMINISTRATION. 29 

tioned, for the shock attending extraction without 
the gas would be more likely to prove- fatal than its 
administration. 

Coleman says : * " Phthisical patients take 
nitrous oxide fairly well, becoming anaesthetized 
with less gas than ordinary patients, as we should 
have anticipated. Anaemic patients do the same." 

In patients of apoplectic tendency or appearance, 
those of full habit, with short, fat necks, there will 
usually be no difficulty, provided the clothing about 
the throat be loose and the head be kept as nearly as 
possible on a line with the body. Respiration is 
more easily interfered with in these than in those of 
slender form. 

Epileptic persons can inhale the gas without 
danger. A seizure may precede or follow the ad- 
ministration, but, of course, cannot occur during it. 
In either case we need but follow the usual course 
of placing the patient in a recumbent position, 
loosen the clothing, and see that there is not too 
long a suspension of heart action. On one occa- 
sion in the author's practice, a girl was seized 
with an epileptic fit as he was about to apply the 
forceps for the extraction of a tooth. After recov- 
ery the gas was administered and the tooth ex- 
tracted with the most satisfactory results. 

Hysterical patients, while recovering from the 
influence of the gas, often give way to their pre- 



*P. 336. 



30 NTTROUS OXIDE. 

vailing emotions in a manner calculated to alarm a 
novice, but experience will show that no danger 
need be apprehended from their manifestations. 

Alcoholism is a condition that the author has 
found to be very unfavorable for the administration 
of the gas. If the patient be a confirmed drinker, 
no untoward results may follow, but a greater quan- 
tity of the gas will need to be given in order to 
produce anaesthesia. If he be only an occasional 
drinker, and happens to be somewhat under the in- 
fluence of liquor at the time, gas should be denied 
him, as most likely it will only serve to increase his 
already excited condition, and he may do violence 
to the operator or to himself. One experience of 
this kind will be sufficient for a lifetime, as the 
author knows from a case in his own practice. 

Idiosyncrasy. — This peculiarity is so common, 
and its manifestations so various, that it would be 
difficult to treat it in detail. The administrator of 
gas often encounters it in persons who declare that 
they never have been and cannot be brought under 
its influence. That such a condition could exist we 
may not be justified in denying, but with pure gas, 
properly administered, we do not see how any ordi- 
nary constitution can successfully resist its influ- 
ence, though some, as we know, are more suscepti- 
ble to it than others. Many operators of largest 
experience in the use of gas declare that they have 
never met with a case where anesthetization was 
impossible, although in some cases those ansesthet- 



ADVISABILITY OF ADMINISTRATION. 31 

ized declared in advance that they could not be 
brought under the influence. 

Menstruation has proven to be no bar to the ad- 
ministration of the gas. No ill results have been 
known to follow on such occasions. 

Pregnancy, not later than the seventh month, 
has been found not to be interfered with by the ex- 
traction of a few teeth under the influence of the 
gas. Later than the seventh month might be safe 
also, but the author has never attempted it and has 
always advised against it. Extraction, with or 
without an anaesthetic, should be postponed, if pos- 
sible, until after confinement. 

Lactation does not contra-indicate the exhibition 
of the gas. Mr. Braine * mentions two cases in 
which the shock attending extraction of a tooth 
without the gas stopped the secretion of milk, 
whereas the same patients underwent similar opera- 
tions a little later, under the influence of the gas, 
without any ill results. 

Age seems to present no barrier to the use of 
nitrous oxide. It may be given (other conditions 
being favorable) as early as the child can be made 
to inhale properly or quite late in life. Mr. Braine 
states that he has given it to a patient at the age of 
ninety-four. The author has administered it to 
patients three years of age and again to those of 
nearly eighty. 



* Journal of British Dental Association. 



32 



NITROUS OXIDE. 



CHAPTER YI. 



MANUFACTURE. 

The apparatus required for the manufacture of 
nitrous oxide consists of a retort or alembic, several 
wash bottles and a receiver or holder. 

The retort should be of strong glass, fitted with 
a ground-glass stopper at neck, where the charge is 
introduced. In use it should be seated in a sand- 
bath, which, in turn, should rest upon a gas stove. 
To maintain its upright position 
the retort should be supported at 
its neck b y attachment to an arm of 
a retort stand, or other suitable ap- 
pliance. 

The wash bottles should be of 
the form known as Wolfe's bottles 
(having two or three necks,) or 
halfgallon bottles with a single 
wide mouth fitted with a rubber 
cork having two perforations for 
the reception of the bent glass 
tubes as shown in Fig. 1. In two of 
the bottles, the longer tube should p IG . 1# 

reach nearly to the bottom of the bottle, and should 




MANUFACTURE. 33 

preferably terminate in a bulb pierced with numerous 
holes for the breaking up of the column of gas into 
bubbles to facilitate the process of washing or puri- 
fication. 

The holder or tank, together with the receiver, 
may be made of sheet zinc, galvanized iron or 
copper (nickel-plated). The receiver, which is open 
below, should fit loosely into the holder and be sup- 
ported by means of cords and pulleys attached to an 
upright framework which is fastened to the holder. 
The free or outside ends of these cords should have 
attached to them suitable weights to counter-balance 
the weight of the receiver. The holder should 
have a capacity of about fifty gallons. A metallic 
tube of one inch diameter should extend from the 
upper edge of the holder along its outside to the 
lower edge, thence along the bottom to the centre, 
there entering the holder and extending upward to 
a level with the top. The upper outside termination 
of this tube is supplied with a faucet which is closed 
when the gas is being manufactured, and opened 
when it is to be inhaled. This same tube has 
another faucet at the base of the holder which is 
open during the elimination of the gas and closed 
during its administration. Another faucet is at- 
tached to the holder at some point of its base for 
the purpose of emptying it when this becomes ne- 
cessary. 

Wash bottle No. I (see cut,) should be empty, as 
it is simply a drip-bottle, and the tubes need rrot ex- 




Fig. 2. 



MANUFACTURE. 35 

tend far through the cork. Bottle No. 2 should 
contain a quart of water in which four ounces of 
ferrous sulphate have been dissolved. Bottle No. 3 is 
charged with a solution of one and a half ounces of 
caustic potassa in a quart of water. The bottles 
should be connected with each other (the short tube 
of one with the long tube of the other), and to the 
retort by means of rubber tubing. A rubber tube 
should also connect the short tube of bottle No. 3, 
with the lower tube faucet. 

The holder should be filled to within a few inches 
of the top with pure soft water. Removing the 
weights from the cords and opening the upper 
faucet of the holder, the receiver will settle to the 
bottom of the holder by its own weight, after which 
all faucets should be closed and the weights re- 
adjusted. 

The retort, charged with about one-and-a-half 
pounds of ammonium nitrate, (the granulated being 
the form most convenient for introduction) should 
be placed in a sand-bath resting on the gas stove, 
and after being connected with wash bottle No. 1, 
heat may be applied. 

As soon as the salt begins to melt, the lower 
tube-faucet should be opened to permit the entrance 
of the gas into the receiver. The elimination of the 
gas will begin as soon as the fused salt begins to 
boil or bubble, and its passage to the receiver will 
be indicated by the bubbling in the second and third 
wash bottles. 



36 NITROUS OXIDE. 

The salt fuses at about 220° F., and at 470 ~ to 
4S0 : the gas is evolved. When this point is reached 
the heat should be kept as uniform as possible until 
the close of the operation, to avoid the formation of 
the dangerous gases N, 2 and N 2 3 . The forma- 
tion of the former is indicated by cloudy fumes in 
the wash-bottles, and the latter by the presence of 
orange-colored vapor. These latter gases are given 
off at a temperature of 500 : and over. 

When the desired quantity of nitrous oxide has 
been generated, the heat should be cut off, the tubing 
between the first and second wash-bottle detached, 
and the lower tube-faucet closed. As water absorbs 
about its own bulk of the gas, the first receiver-full 
will disappear if the weights be lessened. A second 
quantity will therefore have to be made before it can 
be drawn upon for administration. This absorption 
of the gas by the water, occurs of course only once 
after each re-filline of the holder with water. Such 
changing of the water need only take place at inter- 
vals of a month or two. The solution in the wash- 
bottles will remain active for weeks, and the ne- 
cessity for renewal will be indicated by the forma- 
tion of a red precipitate in the iron solution, and 
crystals of potassium nitrate in the potash solution. 

The water in the holder, even though saturated 
with nitrous oxide, exerts a purifying influeuce upon 
the gas in the receiver. For this reason, gas 
should not be used immediately after it has been 
made, but should be allowed to stand for six hours 
or more before being administered. 



MANUFACTURE. 37 

It has been claimed by some that gas should only 
be used while "fresh," and for this reason should 
be manufactured daily. It has never been proven 
that gas undergoes any deterioration when con- 
tained in an air tight receiver over water, nor do 
we see how this can take place. 

LIQUIFIED NITROUS OXIDE. 

The time and care required in the manufacture of 
nitrous oxide, together with the bulkiness of the 
necessary apparatus, has led to its general abandon- 
ment since the manufacture and liquifaction have 
been entered into on a commercial scale by certain 
dental firms. 

The manufacture of gas for liquifaction is con- 
ducted in the same manner as that already de- 
scribed, except on a larger scale. Instead of glass, 
iron retorts lined with porcelain are used, 
and every care is exercised both in the matter of 
preparation and purification to produce as pure an 
article as possible. For condensing the gas, a pump 
worked by steam is used and by it the gas from the 
gasometer is-forced by slow and regular action into 
the iron cylinders and thus liquified. As previously 



For eight years previous to the introduction of liquified 
gas the author manufactured his own gas and administered 
it daily. Occasionally, during a temporary absence, gas 
would remain in the receiver for two or three weeks, and 
when administered invariably produced as satisfactory re- 
sults as gas only a day old. 



38 



NITROUS OXIDE. 



stated a temperature of 45° F. must be maintained 
to bring about the result, and to this end during 
the charging of the cylinders they are kept in ice 
and water, which serves additionally to carry off 
the heat developed in the condensation. 

After the cylinder is charged with its proper 
amount, the tight-fitting valve with which it is pro- 




Pre. 3. 



MANUFACTURE. 



39 



vided is closed, and the cylinder disconnected from 
the pump. About fifteen minutes are required to 
charge a hundred gallon cylinder and a proportion- 
ally longer time for one of larger dimensions. The 
cylinders are heavy wrought iron tubes with top 
and bottom welded in, and to insure tightness are 
tested under heavy hydraulic pressure before being 
used. 

Gas in this form can be transported anywhere, 
and accommodation for the small cylinder is easily 




Fig. 4 



-:: 



>T7B-:rs :x.::i. 



found in an y office. In use it may be s up p orte d 
in a tripod or ornamental stand, {Fig. 3 V ) or 
attached to the wall by a bracket (Fig. 4.) 

For convenience in carrying to the house of a 
patien t, or to a distance, a metal ease, covered with 
morocco, and made large enough to contain not 
only the cylinder, but also the bag, inhaler and 
tubing, is preferred. (Fig. 5.) 





*'IG. (5. 



42 NITROUS OXIDE. 

In offices where the gas is administered on a large 
scale, it is often preferred to allow the gas to 
escape from the cylinder into an ornamental gaso- 
meter holding about ten gallons, and having the 
patient inhale the gas from the gasometer. An ap- 
paratus of this kind, with the cylinder attached, is 
shown in Fig. 6.* 

It is claimed for the gasometer, that in addition 
to the convenience of the large quantity it may con- 
tain, the pressure of the receiver upon the contained 
gas is more uniform than where a bag is used, and 
the inhalation is rendered easier on the part of the 
patient. 

Where gas is administered from an inflated rubber 
bag, as shown in Figs. 4, 5, the pressure during the 
earlier inhalations is excessive, whereas when the 
bag is nearly empty, quite an effort is required on the 
part of the patient to extract the last portions. This 
inequality of pressure is a decided disadvantage, 
and is entirely obviated by the perfectly uniform 
pressure from first to last of the receiver of the 
small gasometers. Another advantage derived 
from the use of the gasometer is economy, for the 
portion of gas unused after one administration is 
retained for future use. In inhaling from a bag, 
the residual portion, if there be any, is necessarily 
lost. 



*A11 the foregoing cuts are introduced by courtesy of 
the S. S. White Dental Mfg. Co., and represent articles 
of their manufacture. 



MANUFACTURE. 



43 



Fig. *l represents a gasometer devised by Dr. A. 
M. Long, of Monroe, Michigan, which is highly en- 
dorsed by those who have used it, and embodies 
many valuable features. Like the one represented 




Fig. 7. 



44 NITROUS OXIDE. 

in Fig. 6, it consists of a water tank or holder 
in which is suspended an inverted receiver with a 
guide-rod in its centre to preserve its upright posi- 
tion. Both holder and receiver are made of thin 
seamless copper tubing, nickel-plated, which affords 
sufficient strength together with lightness. It 
differs from all others of its class in being provided 
with a metal float with soft rubber flange fitting the 
inner periphery of the receiver, thus seeming to 
combine the advantages of a dry gas chamber with 
a wet cistern and sensitive motion. 



INHALERS AND ACCESSORY APPLIANCES. 45 



CHAPTER VII. 

INHALERS AND ACCESSORY APPLIANCES. 

One of the most important adjuncts for the ad- 
ministration of gas is a properly constructed inhaler. 
Even with pure gas and a perfect receptacle for it, 
its use may be fruitless of good results or attended 
with serious difficulties if the inhaler be faulty in 
principle or construction. The requisites of a good 
inhaler are, that it be perfectly air-tight in its fit- 
tings ; that it be of sufficient calibre to admit a full 
volume of gas ; that its valves be free in action and 
tight when closed ; and that it be so formed as to fit 
the face perfectly. It should also be provided with 
a simple yet accurate cut-off to prevent the escape of 
gas at the close of the administration. 

Any admixture of air occurring through imper- 
fection of the appliance or carelessness of the opera- 
tor will either very much delay or wholly prevent 
the desired result. The .calibre of the tubing and 
inhaler is also of great moment. It should be large 
enough at every point to permit the passage of a 
volume of gas sufficient for full and easy inhalation 
on the part of the patient. The lividity of the 
countenance, and especially of the lips and eyelids, 



46 NITROUS OXIDE. 

so noticeable in the earlier days of gas administra- 
tion, was undoubtedly due to the fact that the 
patient received the gas at each inhalation in such 
limited quantity that partial asphyxiation took place 
before the anaesthetic stage was reached. Since the 
introduction of improved inhalers of larger calibre, 
this appearance of asphyxiation is almost entirely 
done away with. With the larger volume of gas 
available and the unlabored action of respiration the 
full anaesthetic stage is reached before asphyxiation 
can take place. 

The first inhalers made were provided with a hard 
rubber mouth-piece. To prevent the inhalation of 
air in its use the lips were held in contact with it by 
means of several fingers of both hands of the oper- 
ator, while the nostrils were closed by the pressure 
of some of the remaining fingers. This method 
was not only exceedingly inconvenient for the oper- 
ator, but also uncomfortable as well as alarming to 
the patient by the feeling of suffocation produced. 
The rubber hood now most generally used is an im- 
provement in every way, for while it adapts itself 
readily to the face, covering both mouth and nose 
and allowing inhalation through each, it leaves the 
hands of the operator more free for other service. 

The accuracy and perfect working of the exhaling 
and inhaling valves of every inhaler is a matter of 
the greatest importance, for if they fail in the proper 
performance of their functions, either air will be ad- 
mitted during inhalation, or exhaled nitrous oxide 



INHALERS AND ACCESSORY APPLIANCES. 



combined with carbonic acid gas will be forced back 
into the receiver to be again inspired with the next 




Fig. 8. 

inhalation. Fig. 8 represents the Codman & Shurt- 
leff inhaler, which in the hands of the author has 
proven a very effective instrument. Letter B indi- 
cates the rubber hood, C the outlet and position of 
exhaling valve, E the position of inhalin'g valve, 
and D the two-way stop-cock with thumb lever. 

Fig. 9 illustrates the posi- 
tion and construction of the 
valves in this inhaler. The 
thin, hard rubber disk, C, 
rests against an annular 
metallic flange and is held in 
position and rendered sensi- 
tive by the delicate, hair-like 
spiral spring, A B. 

A more recent inhaler, and 
one combining all the good 
qualities that our present 
knowledge could demand, is, 




48 



NITROUS OXIDE. 




the one represented in Eig. 10, devised and 
manufactured by the S. S. White Dental Manufac- 
turing Company. In it the character of the valves 
is very similar to the one previously described, but 
they are closer together, and the swinging lever on 
the outside operates a cam on the inside of the tri- 
angular box which effectually controls the action of 
both the inhaling and exhaling valves. It is pro- 
vided with the rubber hood, the tubing is of large 
diameter, and the workmanship throughout is of 



INHALERS AND ACCESSORY APPLIANCES. 49 

the best character. Rubber hoods, with an in- 
flatable margin to more perfectly fit the face, have 
been in use for many years in England (Mr. Clover 
having devised the first one) and more recently 
have been introduced into this country. They 
seem to possess an advantage over the plain hood 
in the greater range of adaptability. 

Gags or mouth props are indispensable adjuncts 
in the administration of nitrous oxide gas, for with 
this agent more than with any other, is it necessary 
to keep the jaws mechanically distended daring ex- 
traction. Gags, to be properly efficient and safe, 
should possess the following properties : 

1. They should be strong and indestructible. 

2. They should be easy to cleanse, hence non-ab- 
sorbent. 

3. They should keep their place and not slip. 

4. They should be sufficiently elastic to prevent 
injury to frail teeth. 

5. They should be large enough to be incapable 
of being swallowed, or be protected with a strong 
twine. 

6. There should be a sufficient variety of sizes to 
meet all cases. 

Gags have been made from large bottle corks cut 
to shape, but they are dangerous to use, owing to 
their ready destructibility and the possibility of 
portions of them finding lodgment in the trachea. 
In addition to this, being absorbent, they are neces- 
sarily unclean. This last objection holds equally 



50 NITROUS OXIDE. 

good in reference to those made of wood or felt. 
Wooden gags are also objectionable because they 
are liable to injure frail teeth or those containing 
large fillings in the muscular pressure brought to 
bear upon them. Metal or hard rubber gags, faced 
on the ends with elastic rubber, have found favor 
with many, but all those that the author has met 
with were so slender in their short diameter as to 
seem likely to become dislodged by any lateral move- 
ment of the jaws. 

Many years ago the author devised and con- 
structed a set of three, which he has had in con- 
tinuous use ever since, and which so fully meet 
all the requirements of a gag that he has met with 

nothing better. Fig. 11 repre- 
sents the medium-sized one. 
They are made of partially 
vulcanized rubber, such as is 
used for car springs and 
carriage buffers. The ma- 
"f ig . 11. terial can be bought in bulk 

at the rubber stores and cut to shape and 
made smooth with a knife and vulcanite file. As 
will be seen by the cut, the .two transverse diame- 
ters are nearly equal, while the long diameter varies 
in each one. Two sides, those presenting to the 
tongue and cheek, are flat, while each of the other 
four sides is concave. These concave surfaces are 
to accommodate the teeth or the alveolar ridges, 
and by their shape lateral slipping is entirely pre- 




INHALERS AND ACCESSORY APPLIANCES. 51 

vented. Each gag, by being made concave on the 
ends and two sides, has two heights, either one of 
which may be used. By virtue of this the three 
gags have a range of distension varying from three- 
fourths to one and three-eighths inches. They 
can be readily and perfectly cleansed, are indestruc- 
tible, and, while the teeth may partially compress 
them, they are incapable of injuring the frailest 
tooth. Their size precludes all possibility of being 
swallowed, and hence there is no need of a string 
to prevent any accident of this character. When 
they are to be removed a bent finger will easily 
accomplish it. Their size also admits of at least 
two teeth in each jaw resting on their surface, 
which adds materially to their fixity of position. 

An apron to protect the clothing of the patient is 
necessary and is preferably made from either white 
or black rubber cloth. It should be two feet wide 
by three and a half feet long, cut out at one end to 
fit the neck and provided with tapes to tie at the 
back. 

A hand spittoon is useful for the relief of the 
patient before he is able to use the one by the side 

of the chair. A very neat and 
suitable one is made by the S. 
S. White Co., a cut of which 
is shown in Fig. 12. It should 
be placed near at hand before 
the gas is administered. 




52 NITROUS OXIDE. 



CHAPTER VIII. 

ADMINISTRATION. 

Preceding the administration, certain precautions 
should be taken to insure the best results. Artifi- 
cial teeth, if worn, should be removed. Ladies 
should be instructed to loosen their dress or stays if 
they be at all tight, so as to give free play to the 
organs of respiration. If there be any friend of 
the patient present, she should not be allowed to re- 
main by the chair during the operation, for, should 
she become alarmed at the appearance of the patient, 
she may, by incautious words or actions, excite 
the patient or annoy the operator. If an assistant 
be present, the friend should remain in an adjoining 
room. If the operator be alone, the friend may be 
allowed to remain in the operating room, as far as 
possible removed from the scene of operation. 

It is of the utmost importance that absolute 
silence be observed by everyone present during the 
administration. A few words of instruction or 
encouragement addressed to the patient by the ad- 
ministrator, in a gentle tone, during the first stages 
of anesthetization are sometimes beneficial, but be- 
yond this no conversation should be held. Any 



ADMINISTRATION. 53 

communication between those present, when neces- 
sary, should be made by gesture or facial expres- 
sion. 

Some operators are accustomed to speak to their 
patients during the whole process of anesthetization, 
thus trying to direct their thoughts into pleasant 
channels in order that their dreams may be agree- 
able, bnt the majority of those experienced in the 
administration of anaesthetics, have found it best to 
allow the thoughts or impressions of the patient 
to follow their own course. Nothing is more sooth- 
ing at such times than silence. 

In all cases it is important that an assistant be 
present to aid the operator whenever necessary. 
Some writers insist upon having the assistant ad- 
minister the gas, so as to leave the operator en- 
tirely free. We see no necessity for this ; indeed, 
we prefer to be both the administrator and oper- 
ator, emplojang the assistant only to watch the 
pulse and respiration, to take charge of instruments 
QT accessories as they are discarded, or to control 
the movements of the patient, should this become 
necessary. 

By way of preparation for any emergency that 
may arise, the operator should have close at hand 
and within easy reach certain accessories, An 
artery or tongue forceps to assist in drawing out 
the tongue in cases of threatened asphyxiation, 
is a valuable adjunct. A small napkin, with which 
the tongue may be easily grasped, drawn out and 



54 NITROUS OXIDE. 

securely held, will often prove serviceable where 
there is room to insert the fingers. Nitrite of amyl 
is invaluable in hastening the return to conscious- 
ness and quickening the action of the heart. Aromatic 
spirits of ammonia is also useful to apply to the 
nostrils where recovery is slow. 

All of these, together with any instruments that 
may be needed during the operation, should be kept 
out of sight of the patient to prevent any unneces- 
sary alarm. Forceps especially should be kept 
carefully concealed until the patient has lost con- 
sciousness. The less display of appliances the bet- 
ter for both patient and operator. 

When the gas is to be administered the patient 
should be made to occupy a position in the chair 
comfortable to himself and favorable to the oper- 
ator. A careful examination of the mouth should 
next be made and a mental note taken of the differ- 
ent teeth to be extracted, their position and sur- 
roundings, and their relative ability to stand the 
pressure of the forceps without breaking. The 
operator should also decide the order in which each 
should be removed. This being done, while the 
assistant is arranging the apron and other details 
the operator should open the instrument drawer and 
quietty arrange his forceps in the order in which 
they will be needed. At the same time he should 
consider the possibility of breakage or other acci- 
dent, and, to meet such emergencies, should also 
arrange in proper order any accessory instruments 



ADMINISTRATION. 55 

that may be needed, after which the drawer should 
again be closed. With proper care all this may be 
done without attracting the patient's attention. 

The gas should now be drawn from the cylinder 
into the intermediate bag or gasometer. Before 
beginning the administration, the operator should 
endeavor to calm any fears the patient may have 
by assuring him of the safety of the agent and ex- 
plaining to him the pleasant and delightful sensa- 
tions he will probably experience during the inhala- 
tion. He should also be instructed to breathe 
slowly and naturally and to make deep and full 
(though not labored) expiration and inspiration. 
If timidity be still noticeable in the patient it is 
often well to apply the inhaler to one's own face, 
and, by inhaling and exhaling through the exhaling 
valve, illustrate the manner of the operation. 

The apron having been adjusted, and all being in 
readiness, the prop or gag should be introduced and 
placed in such position as to keep the mouth well 
open and be as much as possible out of the way of 
the operator. 

The face-piece or hood of the inhaler should now 
be adapted to the face of the patient and he be re- 
quested to breathe. For a few seconds, or until he 
has acquired the proper manner of respiration, the 
patient should be allowed to breathe only the air 
through the exhaling valve. This will inspire con- 
fidence and allow time for the further allaving' of 
any fear. This accomplished, the lever controlling 



56 NITROUS OXIDE. 

the inhaling valve should be gently and cautiously 
opened and the gas admitted. If all goes well, as 
it should, the patient will continue the breathing 
without interruption until the anaesthetic stage is 
reached. It sometimes happens that the patient. 
when beginning to take the gas, will make labored 
movements of the chest simulating those of resoira- 
tion, will grow red in the face, and then, forcibly 
removing the inhaler, complain of a feeling of suf- 
focation and an inability to breathe. If the valves 
of the inhaler be all right and there be no interfer- 
ence with the flow of gas, we may be assured that 
the difficulty complained of rests with the individual 
and not with the apparatus. It is caused by the 
involuntary closure of the larynx, brought on by 
fear or lack of confidence ; this should be explained 
to the patient, and an effort made to restore confi- 
dence, after which, upon a second trial, all will prob- 
ably proceed satisfactorily. 

Should the patient at any point of the procedure 
offer resistance to the continuance of the adminis- 
tration, he should be gently cautioned to keep quiet 
and assured that all is well. Should this not avail, 
and consciousness be still present, it is better to 
cease the administration and allow the patient to 
recover. If force be used or an effort made to re- 
strain the movements of the individual under the 
above conditions it will only serve to terrify him 
and increase his struggles for release. If, however, 
such movements of the patient should occur after 



ADMINISTRATION. 5 7 

consciousness is gone and when he is almost anaes- 
thetized, his movements should be restrained by the 
assistant and the administration pushed to comple- 
tion. Good judgment on the part of the operator 
is needed to determine the exact condition of the 
patient when struggling or resistance begins, so 
that it may be treated in the proper manner. In 
the one instance the resistance is caused by fear, in 
the other it is due to some dream or unconscious 
mental impression. 

When the gas is exhibited under favorable condi- 
tions the character of the respirations at the outset 
will continue the same until near the close of the 
operation. As complete anaesthesia is approached 
the breathing will usually become more rapid, and 
this will be followed in most cases by spasmodic or 
jerky inhalations very similar to snoring in natural 
sleep. The countenance will also usually give indi- 
cation of the progress toward the anaesthetic state. 
The natural color at the beginning will gradually 
give way to pallor, w T hich will continue while the 
effects last. This pallor is also sometimes accom- 
panied by a greater or less lividity of the eye-lids 
and lips, though this is less likely to be manifested 
when the supply tubing is of large diameter and the 
valves of the inhaler of such a character as to ad- 
mit a full and free supply of gas. This lividity, as 
explained in a previous chapter, is due to lack of 
oxygenation of the blood and is the precursor or 
beginning of asphyxia. It usually does not occur 



58 NITROUS OXIDE. 

until the snoring is noticed, and both of these ; 
when present, are indications of complete anaes- 
thesia and require the suspension of the adminis- 
tration. 

Muscular twitching of the extremities is also fre- 
quently noticeable as the anaesthetic state is ap- 
proached, but no special significance is attached to 
it. 

Complete anaesthesia, when attained, may be 
recognized by certain diagnostic indications : 

1. If lividity of the lips and eye-lids be noticed 
we may feel sure that unconsciousness is near at 
hand, and to carry the administration much farther 
would be hazardous. 

2. When the snoring * becomes marked it affords 
us an infallible sign that the full anaesthetic stage is 
reached. 

3. The passing of the hand or finger rapidly be- 
fore the open eye of the patient, without touching 
it, will indicate to us by the non-closure of the eye- 
lid that unconsciousness is complete. 

The first two indications are the most reliable and 
readily discernible, but if they leave as in doubt, 



*The snoring occurring as the anaesthetic stage is reached 
should not be confounded with the stertor preceding 
death. The former is physiological, the latter pathologi- 
cal. Snoring arises simply from a relaxed state of the 
muscles of the palate region. Stertor takes place in the 
larynx and indicates that -lie recurrent pharyngeal branch 
of the pneumogastric nerve is affected. 



ADMINISTRATION. 5 9 

the third will assist us in deciding when the admin- 
istration should be suspended. 

Possible Complications. — The two most serious 
complications that may attend or follow the ad- 
ministration of an anaesthetic, are the arrestation of 
the action of the heart or of the organs of respira- 
tion. In all cases these need to be watched for and 
carefully guarded against. To this end it should 
be the duty of the assistant to carefully watch the 
action of both organs and give notice to the oper- 
ator whenever any unusual symptoms occur. In 
the early stages of the administration the pulse will 
rise considerably from the stimulative effect of the 
agent. After ward it will gradually fall to or nearly 
to the normal standard. Should it fall below nor- 
mality there will be just cause for alarm, and if, in 
connection with this, the breathing should become 
labored and diminished in frequency, a crisis is at 
hand which will require all oar efforts to be devoted 
to the resuscitation of the patient. If taken in 
time, the application of ammonia to the nostrils or 
the inhalation of nitrite of amyl will speedily re- 
store the patient to consciousness. Failure in res- 
piration, when it occurs, will in nearly all cases be 
accompanied by increased lividity of the counte- 
nance, indicating asphyxiation. This is most gener- 
ally caused by the dropping of the tongue into the 
fauces, thereby cutting off all inhalation. The 
proper remedy in such cases is to seize the tongue 
with napkin, tenaculum or artery forceps, and draw 



60 NITROUS OXIDE. 

it forward out of the mouth. In all cases of inter- 
ference with heart action or respiration the only 
safety lies in the prompt application of suitable 
remedies, and to this end all such means should be 
readily available. A moment's delay may prove 
fatal to the patient. 

After- Effects. — Fortunately, the administration 
of nitrous oxide is seldom followed by any after- 
effects, and such as are sometimes encountered are 
not of a serious nature. Nausea will occasionally 
occur after recovery, but when it does it is usually 
due to extreme sensitiveness of the stomach or to 
the accidental swallowing of blood. In either case, 
when the first symptoms appear, we may lessen the 
violence of the attack, or prevent it altogether, by 
the administration of a little brandy and water, and 
by affording the patient plenty of fresh air. 

In ether and chloroform administration, attention 
is generally paid to having the patient's stomach 
neither over-full nor empty, as a preventive of nau- 
sea, but with gas this precaution has not been found 
to be necessary, for experience has shown that it 
may be administered at any time of day and under 
all ordinary conditions of the stomach without 
greater liability to nausea in the one case than in 
the other. 

Syncope has sometimes, though rarely, been 
found to follow the administration of gas, but it is 
due in nearly all cases to a predisposition to the ail- 
ment or to the excessive weakness of the patient 
from some constitutional cause. 



EXTRACTION DURING ANAESTHESIA. 61 



CHAPTER IX. 

EXTRACTION DURING ANAESTHESIA. 

Extraction during the anaesthetic state is an oper- 
ation requiring special qualifications on the part of 
the operator. He should be skillful in order that he 
may perform the operation in the best manner, with 
the least injury to the surrounding parts and least 
liability to accident. It has been well said that no 
one should undertake extraction under an anaes- 
thetic until he has acquired considerable skill in ex- 
traction without it. He should be possessed of 
strong and steady nerves, so that he may not lose 
control of himself through excitement. He should 
be quick in his movements to enable him to perform 
the task he has set himself during the continuance 
of full anaesthesia. A clear head, steady nerves, 
and dexterity are all prerequisites to success in this 
branch of practice. 

Unlike operations in general surgery, where anaes- 
thesia is maintained during the continuance of the 
operation, the dental practitioner is obliged (from 
the location of the organs operated upon) to cease 
the administration before his work can begin, so 
that the anaesthetic state is rapidly passing away 



62 NITROUS OXIDE. 

while his operations are being carried forward. For 
this reason no time must be lost or false movement 
made. 

The position r of the operator should be to the 
right of the patient, as it affords him greater facil- 
ity and enables him to firmly grasp the patient's 
head with his left arm and thus steady it. This 
position should never be more than slightly altered, 
and the forceps should, if possible, be of such shape 
as to enable him to grasp any tooth or root in the 
mouth from his one position. Standing in front of 
the patient to grasp a molar on the right side of the 
lower jaw, as is sometimes done, places the operator 
at a disadvantage in the application of his force 
and prevents him from steadying the head with his 
left arm. During anaesthesia the patient's head 
should never be allowed to pass from the control of 
the operator. 

While the position of the patient in the chair is 
practically the same under all circumstances, the 
relatively high or low position of the chair has 
much to do with facilitating the operation. Where 
lower teeth only are to be extracted the chair should 
be low in position to enable the operator to apply 
his power to advantage. This he can best do by 
standing over the patient and slightly back of him. 

Where upper teeth only are to be extracted the 
chair should be so arranged as to bring the patient's 
head about on a level with the operator's breast. 
Where both upper and lower teeth are to be ex- 



EXTRACTION DURING ANESTHESIA. 63 

traded the chair may be placed at a point interme- 
diate between the high and low positions, or it may 
be in its high position and the operator avail him- 
self of the use of stool while extracting the inferior 
ones. The chair, of course, must occupy its one 
position throughout the operation, as time will not 
admit of its being changed. 

The operator should be careful never to begin 
operations until the patient is fully anaesthetized, 
nor should he continue after consciousness begins 
to return. Partial consciousness during any part of 
the operation will cause the patient to become 
alarmed and he may never again consent to being 
placed under anaesthetic influence. Ambition to 
extract a great many teeth under one administra- 
tion has often led an operator to continue his oper- 
ations after they should have ceased, and the result 
has been that the gas has been blamed for ineffi- 
ciency where the operator alone was at fault. 

It is always safer and better in every way not to 
attempt the extraction of too many teeth at one 
time. While our movements should be quick, they 
ought not to be hurried, for accident is .more than 
likely to occur in the latter case. Extraction should 
never proceed too rapidly for the eye to follow 
every movement of the operator's hand. 

In seizing a tooth the forceps should be fitted to 
the neck and then pushed well up under the free 
margin of the gum before pressure is made or re- 
moval attempted. In exerting the force for removal 



G4 NITROUS OXIDE. 

(after the tooth has been loosened in the socket by 
suitable movements) the operator should keep his 
arm as close to his body as possible, for he is thus 
able to apply more power than he otherwise could. 
It is also well to remember that in grasping the for- 
ceps the palm of the hand should never be turned 
upward, for wrist-power is materially lessened by 
such position. 

Lancing the gums, except in the case of wisdom 
teeth, is usually unnecessary where enough of the 
crown remains to be properly grasped. Wisdom 
teeth, owing to the firm attachment of the soft tis- 
sues to their distal surfaces, should be lanced to pre- 
vent the laceration of these tissues. Serious diffi- 
culty has resulted in many cases where this has 
been disregarded. 

Where roots are broken off or decayed below the 
gum line, and are firmly implanted, the gums should 
be lanced in order to enable them to be firmly 
grasped without injury to the soft tissues. The in- 
cision should be made on both the buccal and lingual 
surfaces in a vertical direction, extending about a 
quarter of an inch from the free margin. Lancing 
should, of course, be done before the administration 
of the anaesthetic is begun, and time should be 
allowed for entire cessation of the hemorrhage. 

Some suggestions in reference to the order of ex- 
traction may perhaps be best formulated under the 
following rules : 

1. Where both upper and lower teeth are to be 



EXTRACTION DURING ANAESTHESIA. 65 

extracted, the lower ones should be removed first. 
If the order were reversed, the blood from the sock- 
ets in the upper jaw would obscure the view of the 
lower ones and interfere with their proper removal. 

2. Where several posterior teeth in the same 
locality are to be removed, begin with the one 
farthest back and come forward. 

3. Where teeth are to be extracted from both 
sides of the jaw, begin on the side having the greater 
number or presenting the greater difficulties. The 
importance of this will be apparent when we re- 
member that the gag is always placed on the side 
having the least to be done, for the reason that we 
will have opportunity to do but little after it is re- 
moved. 

4. Where both teeth and roots are to be extracted 
in different locations, it is usually preferable to re- 
move the teeth first. By so doing we are often 
afforded better access to the roots. Sometimes it 
is better to reverse the order. 

5. Where an entire jaw is to be cleared of teeth 
and roots, begin at the back on one side and come 
as far forward as time will permit. At the next 
sitting follow the same order on the opposite side. 
If some teeth in the front part of the mouth still 
remain, they may be removed at the third sitting. 
By dividing a large operation into different sittings 
we not only prevent interference from blood, but 
add greatly to the after comfort of the patient. 

Forceps and Elevators. — While it is important 



66 NITROUS OXIDE. 

that the extracting instruments be sufficient in num- 
ber and variety of form to cover all cases usually 
presenting, it is also most important to use as few 
of them at any one time as possible, since the 
change from one to another involves the loss of val- 
uable time. Forceps with straight beaks and han- 
dles enable the operator to apply the greatest amount 
of force with the greatest safety. Where this form 
cannot be used, as in the lower jaw and posteriorly 
in the upper jaw, the curvatures or angles should be 
as slight as possible consistent with proper adapta- 
tion. A skilful operator will usually employ the 
same pair of forceps for the extraction of the ten 
anterior teeth and another for the six posterior ones- 
in either jaw. While these four pairs, in addition to 
one or two pairs of root forceps, will be all that he 
will use in simple and favorable cases, he must have 
others in reserve for use under special circumstances. 
Among the latter there should be a Physick or a 
Stellwagen forceps for the removal of the lower 
wisdom teeth in difficult cases ; also, forceps with 
very narrow beaks (curved for lower and straight 
for upper) for the removal of teeth crowded out of 
their normal position, or for roots where the crowns 
of adjoining teeth approximate so closely as to leave 
but little room for instrumental application. The 
forceps popularly known as the " cow-horn," for the 
extraction of the lower molar teeth, is an instrument 
of unusual power, but the danger of splitting the 
roots by its slight misapplication, or of allowing the 



EXTRACTION DURING ANESTHESIA. 67 

tooth to escape from its grasp immediately after re- 
moval, is so great as to interdict its use during the 
anaesthetic state. The latter objection might apply 
with equal force to the use of the " Physick," but 
in some cases we cannot as well accomplish the re- 
sult by the use of any other form. The use of 
forceps with spoon-shaped beaks, commonly known 
as "'alveolar forceps," for the extraction of roots, 
cannot be too strongly condemned. By their use 
large sections are cut from the alveolar borders, 
leaving the ridge very irregular and making the 
future adjustment of plates quite difficult. Their 
use accomplishes nothing that may not be accom- 
plished with the narrow-beaked root forceps. 

Elevators, while their use is objected to by some 
operators, are held in great favor by others. The 
author has found them to be of such service in his 
practice that he would be very loth to relinquish 
their use. The principal objection to them is 
that they do not grasp the root, and therefore cannot 
control it after removal ; but, used as they are, 
without previous lancing, in nine cases out of ten 
the root will simply be tipped over out of the socket 
and remain adherent to the ligament on the opposite 
side. The advantage of their use lies in the fact 
that with them we are often enabled to easily re- 
move difficult roots, and sometimes whole teeth, 
without injury to either gum or process. Those 
illustrated in Fig. 13 represent the five forms found 
most useful in the author's practice. No. 1 is 



68 



NITROUS OXIDE. 



intended for the removal of individual roots any- 
where in the upper jaw. After the point is forced 
well between the process and root, a rotary move- 
ment will easily dislodge the latter. No. 2 is used 
on roots of the lower jaw where we wish to push 
them inward toward the tongue. No. 3 is also in- 
tended for roots in the lower jaw, but is used to pull 
the root outward toward the lip or cheek. Nos. 4 
and 5 are right and left instruments and prove ser- 
viceable in many ways, but especially where we 
wish to use an adjoining tooth as a fulcrum. 




Silence being important during the process of an- 
esthetization, it is equally important during the 
period of recovery. The one condition is analogous 
to the other, and in either conversation is liable to 
confuse and alarm the partly bewildered patient. 
The gag, also, should not be removed from its posi- 
tion too soon after the operation is completed, for 



EXTRACTION DURING ANESTHESIA. 69 

the patient is liable to construe it into an attempted 
removal of a tooth, and violent resistance on his 
part may follow. 

As soon as the teeth have been removed the pa- 
tient's head and body should be gently bent for- 
ward, so that the blood may run out into a hand 
spittoon provided for the purpose and not pass 
down into the stomach. 

Should excessive hemorrhage follow extraction, 
it may usually be checked by inserting into the 
socket a tent of lint sprinkled with tannic acid. 
This may be kept in place, when necessary, by a 
compress of lint or linen placed upon it and then 
bandaging the head and jaw to prevent displace- 
ment. 

Should this prove insufficient, pressure should be 
applied to the artery supplying the part at some 
point where it may be reached. 



TO >"T?.'_" ITS OXZDE 



CHAPTER X. 
axzjzvzs anz z;:zj . :-zv;:is. 

Accidents may occur and emergencies certainly 
will arise at times in connection with the admin- 
istration of any anaesthetic. To properly and 
promptly meet them requires that the practitioner 
should understand their variety, their characteris- 
tics, and their means of remed 

Mr. Henry Bewfll says : * "In the event of an 
accident the administrator ought to be able to rec- 
ognize the symptoms and to act instantly. It is 
not enough to render the patient insensible and to 
trust in every case to an unaided recov: 

Dr. J. VT TVhite has very tersely said: "When 
trouble comes to a patient from any cause during 
the anaesthetic state, it is not a good time to hunt 
up information. n 

Although accidents of any kind, associated with 
the administration of nitrous oxide have been re- 
markably few, they do at times occur, and no one 
knows when they may happen at his own hands. 

♦Medical Press and Circular. Reported in Cosmos, Vol. 
XV., p. 328. 



ACCIDENTS AND EMERGENCIES. T 1 

The possibility of their occurrence should ever be 
kept in mind and the means of meeting them be 
always at hand. 

Many accidents may be prevented by a prelimi- 
nary examiuation of the patient and refusal to ad- 
minister in all cases of a doubtful character. 

Others, again (of a mechanical nature), may often 
be avoided by proper care on the part of the oper- 
ator ; while others still, such as paralysis of the 
heart or of the muscles of respiration, we have no 
means of either foreseeing or preventing. 

Accidents of a minor character, or those least 
likely to prove fatal to life, usually occur through 
the lodgment of some foreign body in the larynx 
during the unconsciousness of the patient. Thus 
the broken beak of a forceps, the whole or part of 
a mouth-gag, or a tooth or portion of one, may easily 
be drawn into the trachea unless due care is exer- 
cised by the operator to prevent it. Cases of this 
kind have occurred, resulting, in some instances, in 
serious trouble, and in others causing death. 

In 186*7 a death occurred in the office of Dr. 
Lee,* in Philadelphia, during the administration of 
nitrous oxide. A post-mortem examination re- 
vealed the fact that an ordinary bottle-cork which 
had been used as a mouth-gag had passed into the 
trachea and become lodged there. Cases are not 
very infrequent in which a root or piece of tooth 



^Cosmos, Vol. VIII. , p. 384. 



72 NITROUS OXIDE. 

has been drawn into the trachea, causing sickness 
and trouble until finally dislodged in a fit of cough- 
ing. 

Only a year or two ago the author was called into 
court as one of several expert witnesses to testify 
in a case of this kind. Gas had been administered 
to a patient by a competent practitioner for the ex- 
traction of a number of teeth. The operation was 
performed satisfactorily to the patient and without 
any knowledge of accident on the part of the oper- 
ator. Shortly afterward the patient began to suffer 
from bronchial irritation attended with severe 
coughing and expectoration. The dentist was not 
advised of this, but the patient was treated by her 
physician, without any abatement of the trouble- 
some symptoms. The patient became emaciated, 
and was finally obliged to take her bed under the 
impression that phthisis had set in. Some time later, 
in a violent fit of coughing, the root of a tooth was 
brought up, after which the patient soon regained 
her accustomed health. 

Fortunately, the dentist was acquitted, it having 
been made evident to the jury that such an accident 
might occur to any practitioner, and was not, per 
se, an evidence of lack of skill. 

A case very similar to this is recorded in the 
Dental Cosmos, Yol. XT., p. 478. Other cases of a 
like nature have been met with time and again that 
have not found record in the journals or gained the 
publicity of a law-suit. 



ACCIDENTS AND EMERGENCIES. 7S 

To avoid all such, mouth-gags should be made of 
such substances as cannot be broken, and should be 
of such size as to be incapable of being drawn 
into the air-passages. A root or portion of a tooth 
may at times slip back into the fauces and be drawn 
into the trachea in spite of the greatest precaution 
but every means should be adopted to prevent such 
an occurrence. 

Once having occurred, if the trouble caused be 
not serious, we may wait a time for nature to 
expel the body ; but if the trouble be serious, the 
position of the obstacle should be located as nearly 
as possible and tracheotomy be performed. 

An accident of minor importance, resulting in 
discomfort rather than danger, is luxation of the 
lower jaw. Sometimes, through the looseness of 
the condyloid articulation, and sometimes through 
excessive force applied in the extraction of a tooth, 
the jaw becomes dislocated. Should this occur, re- 
duction is easily accomplished by placing a fulcrum 
between the teeth, as far back as possible, and then 
pressing the chin upward and backward. In this 
way the condyles of the jaw are released from their 
mal-position and caused to slip back into their proper 
place. A fulcrum may be extemporized by using 
one's thumbs, properly protected with a cloth or 
napkin, but a far better plan is to use, instead, two 
rubber bottle corks, which not only resist pressure 
moderately well, but act as rollers in assisting the 
backward movement of the jaw. 



V4 NITROUS OXIDE. 

By far the most serious accident or emergency 
that may arise in connection with anesthetization 
is asphyxia. Its approach will be indicated by in- 
creased and alarming lividity of the countenance 
and a struggle for breath. If continued, the breath- 
ing may become intermittent or cease entirely. It 
may occur through the slipping of some foreign 
body into the larynx ; by the dropping backward 
of the tongue, thus preventing the ingress of air ; 
or by temporary paralysis of the muscles governing 
respiration. 

The first thing to be done is to draw forward the 
tongue with a tenaculum or artery forceps, or nap- 
kin. If this prove insufficient, the finger should be 
inserted to ascertain whether any foreign body has 
dropped into the fauces, and, if so, to remove it. 
Should both these operations prove ineffectual, arti- 
ficial respiration should at once be resorted to. 

In undertaking this, the patient should be lifted 
from the chair and laid upon the floor face upward. 
A pillow or other suitable article (the operator's 
coat folded or rolled will answer in an emergency) 
should be placed beneath the patient's shoulders and 
the head thrown well back. 

The principle involved in artificial respiration is 
the aeration of the blood by artificial means. This 
is accomplished by causing the thorax to alternately 
expand and contract by manual aid, thus simulating 
the natural chest movements. When the chest is 
pressed downward and inward, whatever air there 



ACCIDENTS AND EMERGENCIES. T5 

may be remaining in the lungs is forced out, and 
when by a reverse movement the thorax is expanded 
a vacuum is produced which will cause the air to 
rush in and occupy the space. 

There are several methods of accomplishing artifi- 
cial respiration, but the following are among the 
simplest and best : 

1. Simple Manual Pressure. With the patient 
in position as described, the operator should place 
the palms of both hands on the ribs close to the 
sternum and near its lower end and force them well 
down to empty the lungs. By releasing the pres- 
sure the natural resilience of the parts will cause 
them to resume their former position, thus inducing 
inspiration. These alternate movements should be 
repeated rapidly until the muscles resume their nor- 
mal function and breathing becomes automatic. 
Mr. Harley says : * " Manual pressure equal to 
about thirty pounds may be with perfect safety ap- 
plied to a healthy adult human thorax." Again : 
" The manual pressure ought to be made on the 
lower part of the sternum, for the resilience of the 
thoracic walls is there greatest ; and pressure on 
the abdomen at the same time is not to be omitted, 
or the diaphragm will descend and counteract the 
benefits derived from the pressure made on the lower 
part of the chest." 

2. Howard's Method. This is more forcible and 



*Holmes , System of Surgery, Yol. 3, pp. 104-5. 



76 



NITROUS OXIDE. 



efficient than the method just described. It consists 
in producing contraction of the thorax by means of 
the operator's knee, while expansion is produced by 
pressing the patient's arms upward and backward, 
alternating the two movements as before. The 
position of patient and operator, as well as the 
modus operandi are well illustrated in Fig. 14. Both 




Fig. 14. 

of the methods just described may easily be carried 
out by the operator alone, but where he has the 
assistance of others the following plan may be 
adopted : 

3. Sylvester's Method. This is considered the 
best method of producing artificial respiration and 
is the one most generally resorted to. In it both 
expansion and contraction of the thorax are pro- 
duced by movements of the patient's arms, accom- 
panied by suitable pressure. Mr. Harley says (loc. 



ACCIDENTS AND EMERGENCIES. 



n 



cit.) : " On bringing down the patient's arms they 
should be gently and firmly pressed against the sides 
of the chest, so as still farther to diminish the 
cavity of the thorax. This pressure can be exer- 
cised with greater facility and equal effect by press- 
ing the arms on the lower third of the sternum. 
By alternating the movements of the arms and 




Fig. 15. 

pressure of this kind a regular exchange of air can 
be produced, varying in quantity from thirty to 
fifty cubic inches, an amount more than is requisite 
for the purposes of resuscitation. 

In all cases the respirations should amount to at 
least thirty or even forty per minute. The natural 
respirations are only eighteen per minute, but in 



IS 



NITROUS OXIDE. 



cases of resuscitation, as our>object is to arterialise 
the blood even more rapidly than in health, and as 
we cannot introduce by artificial means the same 
amount of air that is taken in by the normal efforts, 
we must proportionally increase the number of res- 
pirations." 




Fig. 16. 



Figs. 15 and 16, copied from Holmes' Surgery, 
illustrate perfectly the " Sylvester method." 



COMBINED ANAESTHETICS. 79 



CHAPTER XL 

COMBINED ANESTHETICS. 

The combination of different anaesthetic agents in 
order to secure the advantages of each without the 
disadvantages of either has long been a subject for 
experiment. In medical practice various combina- 
tions of ether, chloroform and alcohol have been 
tried for the past quarter of a century or more with 
results that have been approved by some and con- 
demned by others. Ether and chloroform were 
combined in order that the safety of ether and rapid 
action of chloroform might be conjoined, while 
chloroform and alcohol were united so that the de- 
pressing effects of the former might be counteracted 
by the stimulating effects of the latter. Each of the 
various combinations has its advocates and oppo- 
nents, so that medical sentiment to-day is divided in 
regard to the advisability or otherwise of combina- 
tion. It is believed, however, that combination in 
one form or another is growing in favor, and that 
there are quite as many practitioners who use a 
mixture as there are those who use a single agent. 

The efforts to combine nitrous oxide with other 
agents are of rather recent date. The first experi- 



SO NITROUS OXIDE. 

ments in this direction were probably those of M. 
Paul Bert, begun in 1819, in which by combining 
nitrous oxide with pure oxygen he hoped to prolong 
the anaesthetic state and render it suitable for major 
operations. His experiments, however, with the 
combination under ordinary conditions, as well as 
the exhibition of it under increased atmospheric 
pressure, resulted in nothing of practical value. 

The next attempt to use nitrous oxide in connec- 
tion with another agent was made in England. In 
order to overcome or avoid the pungent effect of 
ether vapor upon the glottis, it was suggested that 
the anesthetization should be begun and carried 
forward for a time with nitrous oxide, after 
which ether should be substituted and unconscious- 
ness maintained. To facilitate this operation a 
special inhaler was devised, which seemed to meet 
with much favor. 

Appreciating the value and relative safety of 
nitrous oxide as an anaesthetic, and at the same time 
recognizing the limitation of the anaesthetic state 
produced by it, various attempts have been made in 
this country during the past ten years to combine it 
with some other agent by which its effects might be 
prolonged and its safety not interfered with. 

One of the first, if not the first, combinations of 
nitrous oxide with another agent was introduced 
to the profession many years ago under the name of 
*• Majo's Vapor.'' Being a proprietary article, the 
character of the compound was not made known. 



COMBINED ANESTHETICS. 81 

It was placed upon the market in the ordinary iron 
gas cylinder, ready for use, and when drawn from 
the cylinder the gas or vapor was made to pass 
through a wash-bottle containing a solution of win- 
tergreen either to conceal the real odor of the com- 
pound or to make it more pleasant for the patient 
to inhale. Notwithstanding the secret character of 
the compound, which should have deterred a pro- 
fessional man from employing it, it found a ready 
sale and is to-day quite extensively used in some of 
the Eastern and Middle States. So far as we have 
been able to ascertain, it is the only article of an 
anaesthetic character in which the different consti- 
tuents are combined and compressed in a gas cylinder. 

Usually, where nitrous oxide is used in combina- 
tion with another agent, the pure liquified gas in its 
escape from the cylinder is made to combine with 
the vapor of another anaesthetic agent (usually 
ether or chloroform) in a receptacle intermediate 
between the cylinder and gasometer. 

Fig. 11 represents an attachment for gas cylin- 
ders, devised by Dr. A. M. Long, in which the gas 
is made to combine with the vapor of some liquid 
anaesthetic. C is the combining chamber through 
which the gas passes from the cylinder in the direc- 
tion of the arrow on its way to the gasometer. A 
is the receptacle for the liquid agent. When the 
handle below it is turned half-wav around, the two 
separated tubes meet at B, and one drop of the 
liquid passes down into the combining chamber. As 



82 



NITROUS OXIDE. 



each turn permits the passage of a drop only, the 
administrator knows with exactness the amount he 
is introducing into the chamber. An appliance such 
as this, or one similar in principle, is generally used 
by those who make their combination after this 
manner. 

As to the advisability of combining nitrous oxide 
with some other more potent agent, opinion is 




Fig. 17. 

divided. The bulk of sentiment in the dental pro- 
fession to-day is opposed to it on the ground that 
by introducing a more powerful agent (and neces- 
sarily a more dangerous one) we step aside from 
ground that is relatively safe to that which is less so, 



COMBINED ANAESTHETICS. 83 

and in so doing we imperil the lives of our patients 
to that extent. It is also argued that each anaes- 
thetic agent possesses properties peculiar to itself 
and operates in a manner different from any other 
agent, and that by combining them, in case any un- 
favorable symptoms appear in the process of anes- 
thetization, we are at a loss to know how to apply 
restorative measures, such as we could safely and 
intelligently apply where but one agent is used. 

Those who favor combinations argue that the 
amount of vapor of the more powerful agent is so 
small in comparison with the quantity of nitrous 
oxide with which it is combined that the safety of 
the gas is not impaired by it. They also cite the 
fact that, notwithstanding the many years during 
which such combinations have been in use, no acci- 
dent or unfavorable result has been known to fol- 
low their exhibition either in dental or medical 
practice. 

With a view to ascertaining the record that the 
combination of gas with ether or chloroform had 
made for itself, the author addressed inquiries to 
several dentists who have had large experience in 
that method of practice, and in each case has re- 
ceived replies most favorable in character. 

One gentleman writes : " I always use chloroform 
and alcohol, equal parts, in combination with 
nitrous oxide. From three to six drops of the mix- 
ture with five gallons of gas I find to be about 
the proper proportion. I cannot see any difference 



84 NITROUS OXIDE. 

between the effects of the combination and those of 
simple nitrous oxide except that the former lasts a 
little longer. The recovery in each case seems to 
be equally rapid. I have had no unfavorable or 
unpleasant effects following the administration of 
the combination, and believe it to be quite as safe 
as nitrous oxide alone." 

Another gentleman says : " I use equal parts of 
the best chloroform and absolute alcohol, say from 
one to two drops of the mixture to each gallon of 
gas. By its use I obtain quicker anesthetization, 
while the recovery is a little slower than when gas 
alone is administered. The pulse seems to be firmer 
and stronger under the combination, and there is less 
discoloration of the face. I have had cases where 
the nitrous oxide would not thoroughly anaesthetize, 
but no case in which the combination failed. For 
five years I used simple nitrous oxide, but for the 
past six years have used the above combination and 
greatly prefer it. Have administered it many hun- 
dreds of times without a single unfavorable result." 

Still another writes : "I have used nitrous oxide 
for eighteen years, and during the past five years 
have given it in combination with either chloro- 
form or ether. For three years I used chloroform 
with the gas, but for the last two have used Squibb's 
ether instead, and prefer it. I combine from fifteen 
to twenty -five drops of the ether with five gallons 
of the gas. By using the combination I can extract 
as many as sixteen teeth and roots at one time, 



COMBINED ANAESTHESIA. 85 

whereas with the gas I have seldom been able to 
remove more than five or seven. Patients seem to 
recover from the effects of the combination as 
quickly as from gas. I have had no nausea or other 
unpleasant effects to follow its administration. I 
cannot suppose a case where it would be proper to 
give the gas in which I should hesitate to admin- 
ister the combination. During the past five years 
I have used from eight to twelve hundred gallons 
of gas each year in combination with some other 
agent, and having had no ill results in all that 
time, must consider it quite as safe as any anaes- 
thetic agent can be." 

Coleman, speaking of the combination of ether 
with nitrous oxide (the latter given alone up to a 
certain point, followed by the former), says: * 
" Ether, although no doubt a much safer anaesthetic 
than chloroform, is yet probably less safe than 
nitrous oxide. Owing to its pungent and irritating 
nature, it is less agreeable to inhale than either 
nitrous oxide or chloroform, but this may be over- 
come by employing it as Clover was the first to do, 
viz., in combination with nitrous oxide. Ether 
with nitrous oxide is most suitable for cases in 
which several teeth are to be removed at one sit- 
ting. We think it also well calculated for those in 
which severe after-pain may be anticipated, as in a 
tooth giving rise to alveolar abscess in any of its 



*Loc. Cit., p. 339. 



86 NITROUS OXIDE. 

stages, recovery being less sudden than with nitrous 
oxide alone. With regard to symptoms indicating 
danger, these will be much the same as with nitrous 
oxide alone, though perhaps less apparent, and con- 
sequently requiring greater watchfulness, as with 
ether there is usually less lividity. Whilst the res- 
piration is carefully watched, the pulse must be 
more regarded than with nitrous oxide. In employ- 
ing the ether combination we must look for more 
tendency to vomiting. " 

The author has had no experience with the com- 
bination of nitrous oxide and ether except in an 
experimental way, and therefore is not prepared 
either to approve of or condemn it, but, in view of 
the favorable record it has made for itself in the 
past six years in this country, he is inclined to look 
upon it with favor, and believes that further experi- 
mentation with it will result in a general acknowl- 
edgment of its value in cases where an effect inter- 
mediate between that of nitrous oxide and of ether 
is desired. 



LEGAL CONSIDERATIONS. 



CHAPTER XII. 

LEGAL CONSIDERATIONS. 

While the professional man is ever liable to be 
held legally responsible for any accident or mis- 
chance that may occur in his practice, he is natu- 
rally held to a greater responsibility when any mis- 
fortune occurs to a patient under anaesthetic influ- 
ence. In the one case it happens while the patient 
is in possession of all his faculties, and the fault, if 
there be any, may be partly his own ; in the other 
the patient is unconscious, and the whole responsi- 
bility is necessarily thrown upon the operator. In- 
telligent and right-minded people will not be in- 
clined to blame or bring trouble upon an operator 
for any ordinary accident occurring in the line of 
his duty, but the ignorant and those evilly disposed 
are only too ready to resort to the law to obtain 
compensation for real or fancied injuries. 

In view of this, the practitioner should familiar- 
ize himself with the legal responsibilities under 
which he, as a specialist, is placed.* The law, 

*The author would especially recommend to all dentists 
and physicians a work entitled "Williams on Laws Re- 
lating to Physicians, Dentists and Druggists," by R. J. 
Williams, of the Philadelphia Bar. 



88 NITROUS OXIDE. 

while guarding the interests of the patient, is 
equally watchful of the rights of the practitioner. 
It requires of him that he shall be possessed of 
ordinary skill, and that in the employment of it he 
exercise ordinary care and diligence. It also de- 
mands that he shall be of good moral character. 

In the use of an anaesthetic, it would demand, in 
addition, that he be familiar with the character of 
the agent used, its method of action, complications 
that may be associated with its use, and the reme- 
dial measures with which to meet them. 

In case of death occurring under the influence of 
an anaesthetic, the operator, in order to be free from 
blame in the eyes of the public, as well as the law, 
would have to show that all the above require- 
ments were met, and that all means usually em- 
ployed to prevent such a catastrophe had been 
employed. 

When this can be done, no judge would charge or 
jury decide that the practitioner was responsible tor 
the misfortune. Should the practitioner, however, 
not be able to show that he had exercised " ordinary 
care, diligence and skill," he might be held liable for 
heavy pecuniary damages, or, possibly, be found 
guilty of manslaughter. 

Happily, few deaths have occurred in connection 
with the administration of nitrous oxide, and none 
of them very recently ; but, with all this, it is most 
important that the operator should realize in each 
case the possibility of death occurring, be on the 



LEGAL CONSIDERATIONS. 89 

alert for any unfavorable symptoms, and have at hand 
all means for immediate attempt at resuscitation. 

In case of death resulting in connection with the 
administration of an anaesthetic of a proprietary or 
secret character, the operator could hardly hope to 
escape conviction in a case at law, for it would be 
held, and justly so, that in administering a com- 
pound the character and ingredients of which he is 
ignorant of, any attempt at counteracting the unfa- 
vorable symptoms would necessarily have to be con- 
ducted blindly, and, therefore, unskilfully. 

Scarcely less serious than the charge of man- 
slaughter is that of criminal assault. This charge 
has so often been preferred by females against the 
administrator of an anaesthetic that it becomes all 
important to protect one's self against it. The 
charge may be made maliciously for the purpose of 
blackmail, or it may be made in all honesty by one 
who believes that she has been wronged while in an 
unconscious condition. In most cases (we hope in 
all) it is a delusion caused either by a dream or by 
that confusion of ideas and emotions likely to occur 
during the abnormal state of anaesthesia. In medi- 
cal practice, it is a generally admitted fact that an- 
aesthetics do stimulate the sexual function. To this 
rule nitrous oxide is no exception, as abundant evi- 
dence proves. It is also admitted that this sexual 
stimulation is more frequently induced (under an 
anaesthetic) in females than in males, especially at 
the time of periodical pelvic congestion. These 



90 NITROUS OXIDE. 

facts, taken in connection with the mental disturb- 
ance before alluded to, and the knowledge of the 
patient before passing under the influence that she 
will be entirely at the mercy of the operator, cause 
it scarcely to be wondered at that delusions of this 
character should occur. One writer truly says : 
" Cases have occurred in which the woman was so 
positive that liberties had been taken with her per- 
son during anaesthesia that the testimony of rela- 
tives who were present all the time scarcely sufficed 
to convince her that she was laboring under a delu- 
sion." 

Dr. B. W. Richardson, of London, has related a 
case where the patient, a female, was being operated 
upon by a dentist, and alleged that he had crimi- 
nally assaulted her ; and this statement she persisted 
in, though her own father and mother, Dr. Richard- 
son, and the dentist's assistant were all present 
during the entire time. 

Another case is on record where a woman made 
a similar charge, although her husband was present 
during the wiiole period of anaesthesia. 

Wharton & Stille * relate a case in which, while 
enlarged nymphae were being removed, the woman 
unconsciously went through the movements of sex- 
ual organism in the presence of numerous bystanders. 

The case of Dr. Beale, the Philadelphia dentist, 
is still fresh in the minds of some of the older prac- 



*Medical Jurisprudence. 



LEGAL CONSIDERATIONS. 91 

titioners. After the administration of ether to an 
unmarried woman for the extraction of teeth, he 
was accused by her of criminal assault. Undoubt- 
edly innocent, he was nevertheless convicted of the 
crime upon the unsupported testimony of the 
woman herself, and sentenced to ten years' impris- 
onment, though, fortunately, afterward pardoned. 
Strange to say, a physical examination of her per- 
son at the time or before the trial was not made, 
and thus one of the best evidences of guilt seemed 
to have been entirely overlooked. Fortunately, 
with our present increased knowledge of the action 
of anaesthetic agents, and of the peculiarities attend- 
ing their administration, a similar verdict under 
similar circumstances could scarcely be reached at 
the present day. 

The dentist who confines himself to the use of 
nitrous oxide, and avoids the more powerful agents, 
is not likely to be accused of criminal assault, as 
the duration of the anaesthetic influence is too short 
to admit of such a result. It will not exempt him, 
however, from the possible charge of attempted lib- 
erties, and to avoid this, as well as charges of any 
other character, it becomes his duty to protect him- 
self by always having a third person present when 
he administers an anaesthetic to a female. 

Legal complications may follow accidents of any 
nature occurring at the dentist's hands. Those of 
a minor character, such as luxation of the inferior 
maxilla, injury to the soft tissues, or the lodgment 



92 NITROUS OXIDE, 

of a root or foreign body in the trachea during ex- 
traction under an anaesthetic may be the means of 
causing him much trouble should the patient decide 
to appeal to the courts for indemnity for the injury 
inflicted. 

Our only means of protection against such pos- 
sibilities is to use our best care and skill to prevent 
accidents ; and should they occur, in spite of us, we 
should be able to convince both judge and jury that 
" ordinary care, diligence and skill 77 had been 
exercised. Being successful in this, we need not fear 
the result of the verdict. 

One more consideration, having a legal bearing, 
remains to be noticed, namely, antisepsis. In the 
present light of medical science, the induction of 
disease by transmission has received, and is receiv- 
ing, the attention which its importance demands. 
Although the germ theory of disease has not been 
fully accepted by a large number of medical prac- 
titioners, it has been accepted by so many of 
high standing, and has taken such a firm hold upon 
the general public, that scarcely a surgeon would 
venture to operate without the aid of antiseptic 
treatment in some of its forms. Indeed, a surgeon 
would hardly feel safe from the terror of the law 
did he not employ some means of preventing the 
transmission of disease through the medium of his 
instruments. If this be important for the general 
surgeon it must be equally so for the dental sur- 
geon, for the same conditions exist in both cases. 



LEGAL CONSIDERATIONS. 93 

Cases have occasionally occurred in which the in- 
duction of a disease has been attributed (justly or 
unjustly) to virus transmitted by means of the den- 
tist's instruments. Everyone must recognize the 
possibility of such an occurrence, although the 
probability of it would naturally be very slight. 
Uncleanliness or lack of care in the treatment of 
instruments before or after use would be as likely to 
produce ill results at the hands of the dentist as of 
the surgeon. The virus of syphilis, for instance, 
might be conveyed by means of extracting instru- 
ments from the mucous patch in one mouth to the 
healthy but lacerated gum in another. 

Now and again physicians, in searching for the 
cause of syphilitic lesions in their patients, after 
eliminating all other probable causes, have come to 
the conclusion that the virus must have been con- 
veyed by the dentist's instruments in the extraction 
of a tooth. 

The author is familiar with a case of this nature 
that occurred in one of the New England States 
some years ago. A lady, the wife of a physician, 
went to her dentist and had a tooth extracted. 
Some time afterward symptoms of syphilis began 
to manifest themselves in the falling of the hair, 
mucous patches in the mouth, and well marked 
syphilides on parts of the body. The physician, 
finding no other cause to which to attribute the in- 
fection, concluded that she must have been inocu- 
lated by means of the dentist's forceps. He so in- 



94 NITROUS OXIDE. 

formed the dentist, who, while he doubted the prob- 
ability, could not deny the possibility, and so the 
matter rested. No legal action was taken, but the 
physician and his wife removed to a distant portion 
of the country to hide the seeming disgrace and 
begin life anew among strangers. 

Whether the dentist was really at fault in the 
matter no one can tell, but all such instances empha- 
size the importance of thorough cleanliness in the 
care of dental instruments, and the disinfection, by 
means of mercuric bichloride solution, or other 
germicide, of all such instruments and appliances, as 
necessarily come in contact with open wounds in 
the mouth. 




111 


s 






hi 

HI 


in 


11 


sii 


* HI 


if 4 











BbsmS 

DsraSsOt 




■.■■.■'■■•.■■■•■■'■■■■■.■ 



